Another interpretation of "Praise the Lord, all nations" is that Israel says to the nations of the world, "Praise the Lord!" And the Lord says to Israel, "Praise the Lord!" The groom says, "Praise the Lord!" to the bride, and the bride says, "Praise the Lord!" to the groom. In the future, the nations of the world will also say "Praise the Lord!" at the time when Israel is redeemed from among them, as it is written in Psalms 102:23, "When the peoples are gathered together."
And it says in Psalm 98:2, "The Lord has made His salvation known." Therefore, it is said, "Praise the Lord, all nations." Rabbi said, "Praise the Lord, all nations." Rabbi Shimon asked his father, our holy teacher, and said to him, "Who are all the nations and who are all the peoples?"
He said to him, "All the nations are the Gentiles who enslaved Israel. All the peoples are those who did not enslave them." They said, "What about those who enslaved Israel? If they praise the Lord, how much more so should we, who were not enslaved by them?"
They began to say, "His mercy has prevailed over us." The earth said, "The truth of the Lord endures forever." What is "the truth of the Lord endures forever?" It is the truth of the covenant that God made with our forefathers, as it says in Leviticus 26:42, "And I will remember My covenant with Jacob."