(5) I will not fail thee, nor forsake thee.--Compare Genesis 28:15. And consider Hebrews 13:5 as a combination of the two Old Testament passages.

(6,7) Be strong and of a good courage . . . that thou mayest observe to do according to all the law.--This command to "be strong," repeated again and again to Joshua, may perhaps be taken as reflecting light upon his natural character, which might not have led him to desire so prominent a position. But it may also be observed that courage was especially needed to carry out the conquest of Canaan in the way that was ordered by the law. For a discussion of this question and its difficulties, see Joshua 13

Verse 5. - There shall not any man be able to stand before thee. Literally, no one shall set himself up against thee, i.e., successfully resist thee (ἀντιστήσεται, LXX.). As I was with Moses. Literally, as I have been with Moses: that is to say, was with him and remained with him unto the end. The continuity of the work of God under the old dispensation is thus as clearly marked as that of the new in Matthew 28:20, and John 20:21-23. The promises made to Abraham, the law given to Moses, the gift of a new life in Christ, are so many parts of one great work, and that work the regeneration of mankind. I will not fail thee. Literally, I will not be weak towards thee, relax towards thee. God is ever the same, If His attitude to us be altered, it is not He who has changed, but ourselves.

1:5-9 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.There shall not any man be able to stand before thee all the days of thy life,.... What is promised to the people in common, Deuteronomy 11:25; is here particularly promised to Joshua their general; and which was fulfilled in him, and still more in Christ his antitype, who made an end of sin, destroyed the devil, spoiled principalities and powers, abolished death, and overcame the world:

as I was with Moses, so will I be with thee; to counsel and advise, guide and direct, protect and defend, prosper and succeed; the Targum of Jonathan is, as my Word"was for the help of Moses, so will I be with thee:"

I will not fail thee, nor forsake thee; but grant him his presence, communicate strength unto him, make good his promises, and leave him not till he had made an entire conquest of the land of Canaan, and even not till the end of his days; and was true of Christ in his state of humiliation, in his sufferings and death, and even in the grave, where he was not left so long as to see corruption; as this is applied to particular believers; see Gill on Hebrews 13:5.