Noah in rabbinic literature "Sefer haYashar" describes another method for distinguishing them: the clean animals and fowls crouched before Noah, while the unclean ones remained standing. A difference of opinion concerning Noah prevails also with regard to his entering into the ark. According to some rabbis, Noah's faith was so small that he did not enter the ark until he stood ankle deep in water (Genesis Rabba xxxii. 9); others declare, on the contrary, that Noah waited for God's directions to enter the ark, just as he awaited His permission to leave it (ib. 34.4; Midrash Agadat Bereshit, in Jellinek, "B. H." iv. 11).
Noah in rabbinic literature (the book from which the angel Raziel taught Adam all the sciences), which had been brought to him by the angel Raphael. The construction of the ark lasted fifty-two years; Noah purposely working slowly, in the hope that the people would take warning therefrom and would repent (Pirke De-Rabbi Eliezer l.c.). The "Sefer haYashar" (l.c.), however, assigns only five years for the construction of the ark. Noah could distinguish between clean and unclean animals inasmuch as the ark of itself gave admittance to seven of the clean animals, while of the unclean ones it admitted two only (Sanh. 108b). The