A hundred and twenty years old: the text states that Moses is 120 years old; it is not saying that this is his 120th birthday. In the book itself this is the day when Moses was giving this speech to the Israelites in the plains of Moab. Moses began the first of his addresses on the first day of the eleventh month of the fortieth year after the Israelites left Egypt (1.3, 5).

I am no longer able to go out and come in: that is, “to lead an active life” or “to get about” (New Revised Standard Version). Some, like Good News Translation and Contemporary English Version, take it in the more restricted sense of “to lead,” but the broader sense seems preferable (see 28.6, 19).

You shall not go over this Jordan: this Jordan is natural style in Hebrew, but in many other languages translators will prefer something like “the Jordan River” or even “the Jordan River here in front of you.” This decision by the LORD is referred to in 1.37; 3.27; 4.21-22; and see Num 20.12 for the occasion when the LORD took this decision.

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on Deuteronomy. (UBS Helps for Translators). New York: UBS, 2000. For this and other handbooks for translators see here .