Clarke's Bible Commentary - Deuteronomy 31:8
Verse 8. The Lord-doth go before thee] To prepare thy way, and to direct thee. He will be with thee] Accompany thee in all thy journeys, and assist thee in all thy enterprises.
He will not fail thee] Thy expectation, however strong and extensive, shall never be disappointed: thou canst not expect too much from him.
Neither forsake thee] He knows that without him thou canst do nothing, and therefore he will continue with thee, and in such a manner too that the excellence of the power shall appear to be of him, and not of man.
John Gill's Bible Commentary
Ver. 8. And the Lord, he [it is] that doth go before thee , etc.] The Word of the Lord, his Shechinah, according to the above Targum, and so in the next clause; the same that brought Israel out of Egypt, had gone before them in the wilderness, and now would go before Joshua and them into the land of Canaan: he will be with thee ; to guide and direct, to assist and strengthen, to protect and defend, to give success to his arms, and victory over his enemies: he will not fail thee, neither forsake thee ; not fail to give him counsel and direction, to afford him strength, and to fill him with courage, and to deliver his enemies into his hands; nor forsake him till he had finished the work he was to do, had made a complete conquest of the Canaanites, and settled the people of Israel in their land: fear not, neither be dismayed ; at the number and strength of the enemy, nor at any difficulties that might lie in the way of finishing so great an undertaking, since the Lord would be with him; (see Romans 8:31).
Matthew Henry Commentary
Verses 1-8 - Moses assures Israel of the constant presence of God with them. This i applied by the apostle to all God's spiritual Israel, to encourag their faith and hope; unto us is this gospel preached, as well as unt them; he will never fail thee, nor forsake thee, Heb 13:5. Mose commends Joshua to them for a leader; one whose wisdom, and courage and affection they had long known; one whom God had appointed to be their leader; and therefore would own and bless. Joshua is well please to be admonished by Moses to be strong and of good courage. Those shal speed well, who have God with them; therefore they ought to be of goo courage. Through God let us do valiantly, for through him we shall d victoriously; if we resist the devil, he will flee from us.
Original Hebrew
ויהוה 3068 הוא 1931 ההלך 1980 לפניך 6440 הוא 1931 יהיה 1961 עמך 5973 לא 3808 ירפך 7503 ולא 3808 יעזבך 5800 לא 3808 תירא 3372 ולא 3808 תחת׃ 2865