ער שווימט אין ים התּלמוד.
Er shvimt in yam hatalmud.
He's swimming in the Sea of Talmud.
He's immersed in Talmud study. SOURCE: Stutchkoff, Der Oytser fun der Yidisher Shprakh. The Talmud is an extensive compilation of teachings and opinions of thousands of rabbis over the centuries, covering matters of Jewish law, ethics, philosophy, history, customs, and more.