פירוש על בראשית 18:5

וסעדו לבכם AND SUSTAIN YOUR HEARTS — In the Torah, the Prophets and the Hagiographa we find that bread is the sustenance of the heart. In the Torah. “[And I will fetch a morsel of bread] and sustain your heart.” In the Prophets: “Stay thy heart with a morsel of bread” (Judges 19:5). In the Hagiographa: “And bread that sustaineth man’s heart” (Psalms 104:15). R. Hama said: Here is not written לבבכם but לבכם thus teaching that the evil inclination has no power over angels (Genesis Rabbah 48:11)

FORASMUCH AS YE PASSED BY. Since your path crossed near me, it is not proper that you should not rest a little with me.
So do, as thou hast said. This is an ethical expression indicating that a morsel of bread will be sufficient.⁸⁵Since it should have stated, “We will do as thou hast said,” and instead it says, “So thou do, as thou hast said,” Abraham ibn Ezra takes it to mean “So do, as thou hast spoken: And I will take a morsel of bread, and do not trouble thyself for more.” Thus the language of Rabbi Abraham ibn Ezra.
It may be that the verse is stating, “So shalt thou do to us, that we recline under the tree and pass immediately as we are messengers, and therefore do not detain us by making us come into the tent or lodge with you.”

כי על כן עברתם על עבדכם. We have a similar construction in Genesis 19,8. It is customary for Scripture to omit the word אשר in such instances, although the reader might have expected it.