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- תהלת ה' ידבר פי - what's the origin? 4 answers
In all Artscroll versions of Birkas Hamazon, you will find the 4 pesukim of Tehilas Hashem, Va'anachnu, Hodu laShem and Mi Y'maleil between Shir Hama'alos or Al Naharos Bovel and zimun.
What is the source for saying these pesukim?