8 This book of the law shall not depart out of thy mouth; but thou shalt meditate therein day and night, that thou mayest observe to do according to all that is written therein: for then thou shalt make thy way prosperous, and then thou shalt have good success.
English Standard Version
8 This Book of the Law shall not depart from your mouth, but you shall meditate on it day and night, so that you may be careful to do according to all that is written in it. For then you will make your way prosperous, and then you will have good success.
8 And don't for a minute let this Book of The Revelation be out of mind. Ponder and meditate on it day and night, making sure you practice everything written in it. Then you'll get where you're going; then you'll succeed.
New King James Version
8 This Book of the Law shall not depart from your mouth, but you shall meditate in it day and night, that you may observe to do according to all that is written in it. For then you will make your way prosperous, and then you will have good success.
New Living Translation
8 Study this Book of Instruction continually. Meditate on it day and night so you will be sure to obey everything written in it. Only then will you prosper and succeed in all you do.
Joshua is to make the law of God his rule. He is charged to meditate therein day and night, that he might understand it. Whatever affairs of this world we have to mind, we must not neglect the one thing needful. All his orders to the people, and his judgments, must be according to the law of God. Joshua must himself be under command; no man's dignity or dominion sets him above the law of God. He is to encourage himself with the promise and presence of God. Let not the sense of thine own infirmities dishearten thee; God is all-sufficient. I have commanded, called, and commissioned thee to do it, and will be sure to bear thee out in it. When we are in the way of duty, we have reason to be strong and very bold. Our Lord Jesus, as Joshua here, was borne up under his sufferings by a regard to the will of God, and the commandment from his Father.