Genesis 21:28 Midrash

וַיַּצֵּ֣ב אַבְרָהָ֗ם אֶת־שֶׁ֛בַע כִּבְשֹׂ֥ת הַצֹּ֖אן לְבַדְּהֶֽן׃

And Abraham set seven ewe-lambs of the flock by themselves.

Read midrashic interpretation of Genesis 21:28: and classical rabbinic exegesis.