44 Moses came with Joshua son of Nun and spoke all the words of this song in the hearing of the people. 45 When Moses finished reciting all these words to all Israel, 46 he said to them, “Take to heart all the words I have solemnly declared to you this day, so that you may command your children to obey carefully all the words of this law. 47 They are not just idle words for you—they are your life. By them you will live long in the land you are crossing the Jordan to possess.”
So we skipped completely over chapter 31 where Joshua succeeded Moses as the leader of Israel
7 Then Moses summoned Joshua and said to him in the presence of all Israel, “Be strong and courageous, for you must go with this people into the land that the Lord swore to their ancestors to give them, and you must divide it among them as their inheritance. 8 The Lord Himself goes before you and will be with you; He will never leave you nor forsake you. Do not be afraid; do not be discouraged.”
Later in chapter 31 Moses and Joshua were summoned by God to the tent of meeting where He told Moses (and Joshua) of the future rebellion of the people of Israel when they would prostitute themselves to the foreign gods of the land they are entering (v16) and how in that day I will become angry with them and forsake them; I will hide my face from them, and they will be destroyed. Not good news. And then God said to Moses (v19) “Now write down this song and teach it to the Israelites and have them sing it, so that it may be a witness for me against them. In the last verse of chapter 31 we read (v30) And Moses recited the words of this song from beginning to end in the hearing of the whole assembly of Israel.
Which brings us to our verses for today where the first 43 verses in chapter 32 consist of this song.
The song was to memorized by everyone, so when punishment came they would remember God had foretold in this song what was to come when the children (or the children’s children or grandchildren … ) would no longer obey the words of the law Moses had spoken and written down before Israel crossed into the promised land. However, the last verse of this song speaks of atonement
Rejoice, you nations, with His people, for He will avenge the blood of His servants; He will take vengeance on His enemies and make atonement for His land and people.
The first part of this is quoted by the Apostle Paul in Romans 15:10 when speaking of Christ and first stating
8 For I tell you that Christ has become a servant of the Jews on behalf of God’s truth, so that the promises made to the patriarchs might be confirmed 9 and, moreover, that the Gentiles might glorify God for His mercy. As it is written:
“Therefore I will praise you among the Gentiles; I will sing the praises of your name.”
10 Again, it says, “Rejoice, you Gentiles, with his people.”
Benson’s Commentary goes on to say according to Paul
We are directed to consider it as a prediction of the bringing in of the Gentiles to share the privileges of the gospel, and become one church of God in conjunction with the Jews. Or, if it be translated more literally, according to the Hebrew, Rejoice, O ye nations, (or Gentiles) His people; that is, being now His people, the sense will be much the same. Either way the words seem evidently to relate to the last great deliverance of the Jews, and their conversion to Christianity, and the bringing in of the fullness of the Gentiles, which undoubtedly will be the completion of the divine dispensations, and will spread peace and happiness over all the earth.
I believe we are indeed given a glimpse of the of the end times when all believers will be united in their faith in Jesus. It is a great wonder to see the Father foretelling of His Son to bring atonement for all the disobedience (sin) of all of mankind.