This book of the law shall not depart out of thy mouth That is, thou shalt constantly read it, and upon occasion discourse of it, and the sentence which shall come out of thy month, shall in all things be given according to this rule. Day and night That is, diligently study, and upon all occasions consider what is God's will and thy duty. The greatness of thy place and employments shall not hinder thee from this work, because this is the only rule of thy private actions and public administrations. I command thee I whom thou art obliged to obey: I who can carry thee through every thing I put thee upon: I of whose faithfulness and almighty power thou hast had great experience!
Related Commentaries of Joshua 1:8
Joshua 1:8-9
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.
9 Have not I commanded thee? Be strong and of a good courage; be not afraid, neither be thou dismayed: for the LORD thy God is with thee whithersoever thou goest.