There is no proof of ignorance more common than conceit of knowledge. Much may be known, when nothing is known to good purpose. And those who think they know any thing, and grow vain thereon, are the least likely to make good use of their knowledge. Satan hurts some as much by tempting them to be proud of mental powers, as others, by alluring to sensuality. Knowledge which puffs up the possessor, and renders him confident, is as dangerous as self-righteous pride, though what he knows may be right. Without holy affections all human knowledge is worthless. The heathens had gods of higher and lower degree; gods many, and lords many; so called, but not such in truth. Christians know better. One God made all, and has power over all. The one God, even the Father, signifies the Godhead as the sole object of all religious worship; and the Lord Jesus Christ denotes the person of Emmanuel, God manifest in the flesh, One with the Father, and with us; the appointed Mediator, and Lord of all; through whom we come to the Father, and through whom the Father sends all blessings to us, by the influence and working of the Holy Spirit. While we refuse all worship to the many who are called gods and lords, and to saints and angels, let us try whether we really come to God by faith in Christ.
The happy change whereby the Galatians were turned from idols to the living God, and through Christ had received the adoption of sons, was the effect of his free and rich grace; they were laid under the greater obligation to keep to the liberty wherewith he had made them free. All our knowledge of God begins on his part; we know him because we are known of him. Though our religion forbids idolatry, yet many practise spiritual idolatry in their hearts. For what a man loves most, and cares most for, that is his god: some have their riches for their god, some their pleasures, and some their lusts. And many ignorantly worship a god of their own making; a god made all of mercy and no justice. For they persuade themselves that there is mercy for them with God, though they repent not, but go on in their sins. It is possible for those who have made great professions of religion, to be afterwards drawn aside from purity and simplicity. And the more mercy God has shown, in bringing any to know the gospel, and the liberties and privileges of it, the greater their sin and folly in suffering themselves to be deprived of them. Hence all who are members of the outward church should learn to fear and to suspect themselves. We must not be content because we have some good things in ourselves. Paul fears lest his labour is in vain, yet he still labours; and thus to do, whatever follows, is true wisdom and the fear of God. This every man must remember in his place and calling.