Deuteronomy 31:6

31:6 Be strong and courageous! Do not fear or tremble before them, for the Lord your God is the one who is going with you. He will not fail you or abandon you!”

Deuteronomy 31:23

31:23 and the Lord ¹  commissioned Joshua son of Nun, “Be strong and courageous, for you will take the Israelites to the land I have promised them, and I will be with you.” ² 

[31:23]  ¹ tn Heb “he.” Since the pronoun could be taken to refer to Moses, the referent has been specified as “the Lord” in the translation for clarity. See also the note on the word “you” later in this verse.

[31:23]  ² tc The LXX reads, “as the Lord promised them, and he will be with you.” This relieves the problem of Moses apparently promising to be with Joshua as the MT reads on the surface (“I will be with you”). However, the reading of the LXX is clearly an attempt to clarify an existing obscurity and therefore is unlikely to reflect the original.