Eden:
Regarding "forever," the NAC commentary was saying, in effect, that "to the tenth generation" shouldn't be taken in a numerically literal way. That it had an unending sense to it, or, at least as long as the covenant was in force. (The commentary actually said "basically forever.")
On the the Moabite & Ammonite question, The Bible Knowledge Commentary posits (Vol I, p. 303):
- The treatment of Ruth, however, by Boaz along with other Israelites of Bethlehem demonstrates that this law [Deut 23] was never meant to exclude one who said, "Your people will be my people and your God my God" (Ruth 1:16). Isaiah seemed to have held a similar interpretation (cf. Isa 56:3, 6-8) but perhaps those verses in Isaiah apply only to end times.
The accounts in Nehemiah and Ezra seem to focus on the fact that the "foreign wives" had taken no such stand towards Yahweh worship as Ruth had taken. And, as pagan worshipers, they and their foreign speaking children posed a threat to the future of the restored nation in connection with its standing with Yahweh. (Nehemiah compares them with Solomon taking foreign wives, which he did while they were, and remained, pagan worshipers.)
For the record (and so as not to distract the thread), I'm not commenting here on the morality of dismissing one's children and wife, as the accounts in Ezra and Nehemiah describe. But it should be noted that the law covenant made a distinction between foreigners who took up the worship of Yahweh (e.g. Ruth) and those who didn't. (Compare e.g. Exodus 12:43-49.)
One thing your thread might prompt me to do is get a copy of The Pentateuch and Haftorahs. I gained some interest in it after seeing it referred to in the WT study the other week. Reviews of it at bookseller websites seem to reccommend it as a great resource for the Jewish view of the Law.
Take Care, Eden