The Gentle Rebuke
"These are the words which Moses spoke to all Israel on the other side of the Jordan, in the desert, in the Plains [of Moab], opposite Suf, between Paran, and Tofel, and Lavan, and Hazerot, and Di-Zahav" (Deuteronomy 1:1)
The Book of Deuteronomy opens the Torah's account of how Moses reviewed with his people the forty years they had spent in the desert. In the first verse Moses rebukes Israel by alluding to a number of their rebellious sins against the Al-mighty during the years in the wilderness. Moses, although primarily rebuking the people, managed nonetheless to suggest an excuse within the words of the rebuke itself, to drop a subtle suggestion of extenuating circumstances for each sin, in at least partial defense of Israel's backsliding.
Moses says "in the wilderness," rebuking Israel for her lack of faith when the Jews had exclaimed bitterly "if only we could die in the wilderness" when they had no water. But Moses selects the general term "wilderness" (rather than naming the actual place where the incident occurred -- the Sin Desert between Eilim and Sinai) to suggest that it was a severe test of their faith; they could not be held so guilty for complaining of thirst, for they were in "the great and fearful desert of snakes, serpents and scorpions and arid with no water."
"Plains of Moab"
Moses says "in the plains," referring to the place where the Israelites had allowed themselves to be seduced into idol-worship by the Moabite women. Again Moses does not mention the place-name (Shittim) but emphasizes "the plains" i.e. the well-known Plains of Moab, which had the environmental effect of bringing out the worst Moabite-like immorality in all who traveled there -- a point of defense for the people's conduct.
"Facing the Sea"
Moses says "facing [the Sea of] Soof," rebuking Israel for their lack of faith at the Red Sea. The Egyptian army had trapped them at the seashore and they had exclaimed "was it for lack of graves in Egypt that you brought us to die in the wilderness?!" After all the miracles they had witnessed in Egypt, they failed to show faith in G-d's power to rescue them now. But Moses at the same time hints at the extenuating circumstances by underscoring that they had faced the sea. With the sea in front and the pursuing Egyptians behind there was no natural possibility whatever of being saved. Though superficially rebuking his people, Moses at the same time gently suggested that they could not be harshly indicted for failing such a severe and trying test of faith.
After mentioning several other occasions when the Jews sinned in the desert, Moses concluded with "and at Di Zahay." The word zahav means "gold," and Moses' reproachful reference was to the Golden Calf which they had made -- and worshipped. Yet Moses gently suggests that the (di)abundance of gold and silver the Israelites possessed had turned their heads and led them to sin.