laskern: The GR”A says that the memre is a mistake. when the gemara was printed it said ” kayem avraham avinu kol hatorah kulo afilu “ayin tav” (abbreviation ) which was mistakenly spelled out as eirav tavshulin when it was actually an abbreviation for eirav techumin. as the gemara continues, “shenemar, eikev asher shama b’koli” (devorim asher adam dash b’eikev).
