Joshua 1:8

This book of the law shall not depart out of thy mouth - The law which had already been written by Moses, and from which he and the people were to take all those precepts by which their lives were to be governed. Though there was a copy of the law laid up in the sanctuary, yet this was not sufficient. Joshua must have a copy for himself, and he was to consult it incessantly, that his way might be made prosperous, and that he might have good success. If he kept God's word, God would keep him in body and soul; if he should observe to do according to that word, then God would cause all his way to be prosperous. Those who are obedient to God lack no manner of thing that is good.

THE LORD APPOINTS JOSHUA TO SUCCEED MOSES. (Jos. 1:1-18) Now after the death of Moses--Joshua, having been already appointed and designated leader of Israel (Num 27:18-23), in all probability assumed the reins of government immediately "after the death of Moses." the servant of the Lord--This was the official title of Moses as invested with a special mission to make known the will of God; and it conferred great honor and authority. the Lord spake unto Joshua--probably during the period of public mourning, and either by a direct revelation to the mind of Joshua, or by means of Urim and Thummim (Num 27:21). This first communication gave a pledge that the divine instructions which, according to the provisions of the theocracy, had been imparted to Moses, would be continued to the new leader, though God might not perhaps speak to him "mouth to mouth" (Num 12:8). Joshua--The original name, Oshea, (Num 13:8), which had been, according to Eastern usage, changed like those of Abram and Sarai (Gen 17:5-15) into Jehoshua or Joshua (that is, "God's salvation") was significant of the services he was to render, and typified those of a greater Saviour (Heb 4:8). Moses' minister--that is, his official attendant, who, from being constantly employed in important services and early initiated into the principles of the government, would be well trained for undertaking the leadership of Israel.

This book of the law shall not depart out of thy mouth,.... He was often to read it, frequently repeat it, and speak of it, to refresh his own memory with it, and the memory of those about him. Jarchi restrains it to the book of Deuteronomy now before him: but thou shalt meditate therein day and night; whenever he had any leisure from the important business of his office, whether by day or night, see Psa 1:2, that thou mayest observe to do according to all that is written therein; which frequent speaking of it, and constant meditation on it, would lead unto: for then thou shalt make thy way prosperous, and then thou shalt have good success; in his wars with the Canaanites.

The Preamble - Jos 1:1-9 After the death of Moses the Lord summoned Joshua, the servant of Moses, whom He had appointed as the leader of Israel into Canaan, to go with all the people across the Jordan, and take the land which had been promised to the fathers on oath, assuring him at the same time of His powerful aid, on condition that he observed the law of Moses faithfully. This summons and promise of God form the preamble to the whole book, which is linked on to the conclusion of the Pentateuch by the introductory words, "And it came to pass after the death of Moses, the servant of the Lord," though it is not so closely connected as to warrant the conclusion that the two works have been written by the same author.

The book begins with the history, not of Joshua's life (many remarkable passages of that we had before in the books of Moses) but of his reign and government. In this chapter, I. God appoints him to the government in the stead of Moses, gives him an ample commission, full instructions, and great encouragements (Jos 1:1-9). II. He accepts the government, and addresses himself immediately to the business of it, giving orders to the officers of the people in general (Jos 1:10, Jos 1:11) and particularly to the two tribes and a half (Jos 1:12-15). III. The people agree to it, and take an oath of fealty to him (Jos 1:16-18). A reign which thus began with God could not but be honourable to the prince and comfortable to the subject. The last words of Moses are still verified, "Happy art thou, O Israel! Who is like unto thee, O people?" Deu 33:29.

1:8 This Book of Instruction (Hebrew torah) probably refers to the book of Deuteronomy (see Deut 4:44; 29:21; 30:10; 31:9-12). It includes Israel’s foundational law codes as well as God’s moral and spiritual instructions. • God commanded Joshua to think and speak of God’s instruction day and night—i.e., continually (cp. Deut 6:6-7; 17:18-20).