But it is not only that there is a line of conduct to follow, a model to imitate, a Spirit with whom one may be filled, it is not only relationships between oneself and God, and those in which we stand here below; this is not all that must occupy the Christian. He has enemies to fight. The people of Israel under Joshua in the land of Canaan were indeed in the promised land, but they were in conflict there with enemies who were in it before them, although not according to the rights by which Israel possessed the land through the gift of God. God had set it apart for Israel (see Deut. 32:8); Ham had taken possession of it.
Now, with regard to us, it is not with flesh and blood that we have to fight, as was the case With Israel. Our blessings are spiritual in the heavenly places. We are sitting in Christ in the heavenlies. We are a testimony to principalities and powers in the heavenlies; we have to wrestle with spiritual wickednesses in the heavenlies. Israel had passed through the wilderness-had crossed the Jordan; the manna had ceased; they ate the corn of the land. They were settled in the land of Canaan as though it were all their own without striking a blow. They ate the produce of this good land in the plains of Jericho. So it is with regard to the Christian. Although we are in the wilderness, we are also in the heavenly places in Christ. We have crossed the Jordan, we have died and are risen again with Him. We are sitting in the heavenly places in Him, that we may enjoy the things of heaven as the fruit of our own country. But conflict is before us, if we desire to enjoy them practically. The promise is of every blessing, of all the promised land, but wheresoever we shall set our foot on it (Joshua 1). For this we need the Lord's strength, and of this the apostle now speaks. "Be strong," he says, "in the Lord." The enemy is subtle. We have to withstand his stratagems even more than his power. Neither the strength nor even the wisdom of man can do anything here. We must be armed with the panoply, that is, the whole armour, of God.
But observe first, that the Spirit turns our thoughts upon God Himself before speaking of that which has to be overcome. "Be strong in the Lord." It is not, first of all, a refuge from the face of the enemy; we are in it for ourselves before we use it against the wiles of the enemy. It is in the intimacy of the counsels and the grace of God that man fortifies himself for the warfare from which he cannot escape, if he would enjoy his christian privileges. And he must have the whole armour. To be wanting in one piece exposes us to Satan on that side. The armour must be that of God-divine in its nature. Human armour will not ward off the attacks of Satan; confidence in that armour will engage us in the battle only to make us fall in combat with a spirit who is more mighty and more crafty than we are.
These enemies are thus characterised; they are principalities and powers-beings possessing an energy of evil which has its source in a will that has mastery over those who do not know how to resist it; they have also strength to carry it out. Their energy they have from God, the will that uses it comes from themselves; they have forsaken God; the spring of their actions is in their own will. In this respect it is a source of action independent of God, and the energy and the qualities which they have from God are the instruments of that will-a will which has no bridle except from outside itself. They are principalities and powers. There are good ones; but in them the will is only to do that which God wills, and to employ in His service the strength they have received from Him.
These rebellious principalities and powers rule over the darkness of this world. Light is the atmosphere in which God dwells, which He diffuses all around Himself. Wicked spirits deceive and reign in darkness. Now this world, not having the light of God, is entirely in darkness, and demons reign in it; for God is not there-except in supreme power after all, turning everything to His glory, and, in the end, to the good of His children.
But if these principalities rule in the darkness of this world they do not possess merely an outward force; they are in the heavenlies, and are occupied with spiritual wickedness there. They exercise a spiritual influence, as having the place of gods. There is then, first, their intrinsic character, their mode of being, and the state in which they are found; second, their power in the world as governing it; and third, their religious and delusive ascendency, as lodging in the heavens. They have also, as a sphere for the exercise of their power, the lusts of man, and even the terrors of his conscience.
To resist enemies like these we need the armour of God. The manifestations of this power, when God permits it, constitute the evil days. All this present period of Christ's absence is, in a certain sense, the evil day. Christ has been rejected by the world, of which, while in it, He was the light, and is hidden in God. This power, which the enemy displayed when he led the world to reject Christ, he still exercises over it: we oppose it by the action and the power of the Holy Ghost, who is here during the Lord's absence. But there are moments when this power is allowed to shew itself in a more especial manner, when the enemy uses the world against the saints, darkening the light which shines in it from God, troubling and leading astray the minds of professors and even of believers-days, in a word, in which his power makes itself felt. We have to wrestle with this power, to resist it all, to stand against everything in the confession of Christ, of the light; we have to do all that the confession of His name requires in spite of all and at whatever cost, and to be found standing when the storm and the evil day are past.
Thus we have not only to enjoy God and the counsels of God and their effect in peace; but, since these very counsels introduce us into heavenly places and make us the light of God on earth, we have also to encounter the spiritual wickednesses which are in the heavenly places, and which seek to make us falsify our high position, to mislead us, and to darken the light of Christ in us on the earth. We have to escape the snares of heavenly spiritual wickedness for ourselves, and to maintain the testimony here below incorrupt and pure. 
Now by the power of the Holy Ghost, who has been given to us for this purpose, we shall find that the armour of God relates first to that which, by setting the flesh aside, and by maintaining the existence of a good conscience, takes all hold from the enemy; then, to the preservation of complete objective trust in God; and next, to the active energy which stands with confidence in the presence of the enemy, and using the weapons of the Holy Ghost against him. The defensive armour our own state, comes first. The whole ends with the expression of the entire and continual dependence on God in which the christian warrior stands.
We will examine this armour of God, that we may know it. It is all practical-founded on that which has been accomplished, but in itself practical. For it is not a question here of appearing before the bar of God, but of resisting the enemy, and of maintaining our ground against him.
Before God our righteousness is perfect, it is Christ Himself, and we are the righteousness of God in Him: but we do not need armour there, we are sitting in the heavenly places: all is peace, all is perfect. But here we need armour, real practical armour, and first of all to have the loins girt about with truth. The loins are the place of strength when duly girt, but represent the intimate affections and movements of the heart. If we allow our hearts to wander where they will, instead of abiding in communion with God, Satan has easy hold upon us. This piece of armour is then the application of the truth to the most intimate movements, the first movements of the heart. We gird up the loins. This is done, not when Satan is present; it is a work with God, which is done by applying the truth to our souls in His presence, judging everything in us by this means, and putting a bridle on the heart that it may only move under His eye. This is true liberty and true joy, because the new man enjoys God in uninterrupted communion; but here the Spirit speaks of it with respect to the safeguard which it will be to us against the attacks of the enemy. At the same time it is not merely the repression of evil thoughts-that is its consequence: it is the action of the truth, of the power of God, acting by the revelation of everything as it is-of all that He Himself teaches, bringing the conscience into His presence, keeping it thus in His thoughts; all that God has said in His word, and the unseen realities having their true force and their application to the heart that stirs in us, so that its movements should have their character from God's own word and not from its own desires, everything going on in the presence of God. 
Satan has no hold on a heart thus kept in the truth, as revealed by God; there is nothing in its desires that answers to the suggestions of Satan. Take Jesus as an example. His safeguard was not in judging all that Satan said. In the wilderness at the beginning of His public service, except in the last temptation, it was in the perfect application of the word for Himself, for that which concerned His own conduct, to the circumstances around Him. The truth governed His heart, so that it only moved according to that truth in the circumstance that presented itself "Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God." No word has come forth-He does nothing. There was no motive for acting. It would have been to act of His own accord, of His own will. That truth kept His heart in connection with God in the circumstance that met Him. When the circumstance arose, His heart was already in intercourse with God, so that it had no other impulse than that which the word of truth suggested. His conduct was purely negative, but it flowed from the light which truth threw upon the circumstance, because His heart was under the absolute government of the truth. The suggestion of Satan would have brought Him out of this position. That was enough. He will have nothing to do with it. He does not yet drive away Satan: it was only a matter of conduct, not of flagrant opposition to the glory of God. In the latter case He drives him away; in the former He acts according to God without concerning Himself with anything farther. Satan's device totally failed of its effect. It simply produced nothing. It is absolutely powerless against the truth, because it is not the truth; and the hearth has truth for its rule. Wiles are not the truth: this is quite enough to prevent our being caught by them, that is, if the heart be thus governed.
In the second place there is the breastplate of righteousness-a conscience that has nothing to reproach itself with. The natural man knows how a bad conscience robs him of strength before men. There is only to be added here the way in which Satan uses it to entrap man in his snares. By maintaining the truth we have Satan for our enemy. If we yield ourselves up to error, he will leave us in that respect at peace, except in using our faults and crimes to enslave us more, to bind us hand and foot in that which is false. How would a man who has the truth, who has perhaps even escaped error, if his conduct were bad, bear to have it exposed to the eyes of all? He is silent before the enemy. His own conscience even will make him silent, if he is upright, without thinking of consequences, unless a confession be necessary. Besides this the strength of God and spiritual understanding will fail him: where could he have gained them in a wrong walk? We go forward boldly when we have a good conscience. But it is when we are walking with God, for the love of God, for the love of righteousness itself, that we have this breastplate on, and thus we are fearless when called to go forward and face the enemy. We gain a good conscience before God by the blood of the Lamb. By walking with God we maintain it before men and for communion with God, in order to have strength and spiritual understanding, and to have them increasingly. This is the practical strength of good conduct, of a conscience without rebuke. "I exercise myself" always to this, said the apostle. What integrity in such a walk, what truthfulness of heart when no eye sees us! We are peremptory with ourselves, with our own hearts, and with regard to our conduct; we can therefore be peaceful in our ways. God also is there. So walk, says the apostle, and the God of peace shall be with you. If the fruits of righteousness are sown in peace, the path of peaceis found in righteousness. If I have a bad conscience, I am vexed with myself, I grow angry with others. When the heart is at peace with God and has nothing to reproach itself with, when the will is held in check, peace reigns in the soul. We walk on the earth, but the heart is above it in intercourse with better things; we walk in a peaceful spirit with others, and nothing troubles our relations with God. He is the God of peace. Peace, the peace of Jesus, fills the heart. The feet are shod with it; we walk in the spirit of peace.
But, together with all this, a piece of defensive armour is needed over all the rest, that we may be able to stand in spite of all the wiles of the enemy-an armour, however, which is practically maintained in its soundness by the use of the preceding ones, so that, if the latter is essential, the others have the first place in practice. This is the shield, faith; that is to say, full and entire trust in God, the consciousness of grace and of His favour maintained in the heart. Here faith is not simply the reception of God's testimony (although it is founded on that testimony), but the present assurance of the heart with regard to that which God is for us, founded, as we have just said, on the testimony which He has given of Himself-trust in His love and in His faithfulness, as well as in His power. "If our hearts condemn us not, then have we confidence towards God." The work of the Spirit in us is to inspire this confidence. When it exists, all the attacks of the enemy, who seeks to make us believe that the goodness of God is not so sure-all his efforts to destroy or to weaken in our hearts this confidence in God and to hide Him from us, prove fruitless. His arrows fall to the ground without reaching us. We stand fast in the consciousness that God is for us: our communion is not interrupted. The fiery darts of the enemy are not the desires of the flesh, but spiritual attacks.
Thus we can hold up our heads: moral courage, the energy which goes forward, is maintained. Not that we have anything to boast of in ourselves, but the salvation and the deliverance of God are fresh in our minds. God has been for us; He is for us: who shall be against us? He was for us when we had no strength; it was salvation, when we could do nothing. This is our confidence-God Himself-not looking at ourselves. We have the helmet of salvation on our heads. The former parts of the armour give us freedom to enjoy the two latter.
Thus furnished with that which protects us in our walk, and in the practical confidence in God, and the knowledge of God that flows from it, we are in a state to use offensive weapons. We have but one against the enemy, but it is one that he cannot resist if we know how to handle it: witness the Lord's conflict in the wilderness with Satan. It is the word of God. There Jesus always answered with the word by the power of the Spirit. It sets man in his true position according to God as obedient man in the circumstances around him. Satan can do nothing there: we have but to maintain that position. If Satan openly tempts us to disobedience, there is no wile in that. Not being able to do anything else, Satan acted thus with the Lord, and manifested himself as he is. The Lord drove him away by the word. Satan has no power when he is manifested as Satan. We have to resist the wiles of the devil. Our business is to act according to the word, come what may; the result will shew that the wisdom of God was in it. But observe here, this sword is the sword of the Spirit. It is not the intelligence or the capacity of man, although it is man who uses the word. His sword is highly tempered, but he can neither draw it nor strike with it if the Holy Ghost is not acting in him. The weapons are spiritual; they are used by the power of the Spirit. God must speak, however weak the instrument may be.
The sword is also used actively in the spiritual warfare, in which it judges all that is opposed to us. In this sense it is both defensive and offensive. But, behind all this armour, there is a state, a disposition, a m eans of strength, which quickens and gives all the rest its power: this is a complete dependence on God, united to trust in Him, which expresses itself in prayer. "Praying always"; this dependence must be constant. When it is real, and I feel that I can do nothing without God, and that He wills my good in all things, it expresses itself. It seeks the strength which it has not: it seeks it from Him in whom it trusts. It is the motion of the Spirit in our hearts in their intercourse with God, so that our battles are fought in the communion of His strength and His favour, and in the consciousness that we can do nothing, and that He is all. "At all times"; "with supplication." This prayer is the expression of the man's need, of the heart's desire, in the strength that the Spirit gives him, as well as in confidence in God. Also since it is the Spirit's act, it embraces all saints, not one of whom can be forgotten by Jesus; and the Spirit in us answers the affections of Christ, and reproduces them. We must be watchful and diligent in order to use this weapon; avoiding all that would turn us away from God, availing ourselves of every opportunity, and finding, by the grace of the Spirit, in everything that arises, an occasion (by means of this diligence) for prayer and not for distraction.  The apostle asks from his heart for this intercession on their part, in the sense of his own need and of that which he desires to be for Christ.
The mission of Tychicus expressed Paul's assurance of the interest which the love of the Ephesians made them take in having tidings of him, and that which he himself felt in ascertaining their welfare and spiritual state in Christ. It is a touching expression of his confidence in their affection-an affection which his own devoted heart led him to expect in others.
He presents the Ephesians as enjoying the highest privileges in Christ, and as being able to appreciate them. He blames them in nothing. The armour of God-by which to repel the assaults of the enemy, and to grow up in peace unto the Head in all things, the preservative armour of God-was naturally the last thing that he had to set before them. It is to be noticed that he does not speak to them in this epistle of the Lord's coming. He supposes believers in the heavenly places in Christ; and not as on earth, going through the world, waiting till He should come to take them to Himself, and restore happiness to the world. That which is waited for in this epistle is the gathering together of all things under Christ, their true Head, according to the counsels of God. The blessings are in the heavens, the testimony is in the heavens, the church is sitting in the heavens, the warfare is in the heavens.
The apostle repeats his desire for them of peace, love, and faith; and concludes his epistle with the usual salutation by his own hand.
This epistle sets forth the position and the privileges of the children, and of the assembly in its union with Christ.