Avraham sat at the door of his tent in the heat of the day, by the oaks of Mamre. He looked up and saw three travelers standing nearby, and he ran to greet them and bowed to the ground.
וַיִּשָּׂא עֵינָיו וַיַּרְא וְהִנֵּה שְׁלֹשָׁה אֲנָשִׁים נִצָּבִים עָלָיו וַיַּרְא וַיָּרׇץ לִקְרָאתָם מִפֶּתַח הָאֹהֶל וַיִּשְׁתַּחוּ אָרְצָה׃
בראשית יח:ב
"He lifted his eyes and looked, and behold, three men were standing over him. He saw, and he ran to greet them from the door of the tent, and bowed down to the ground."
Bereishis 18:2
He hurried to bring them bread, butter, milk and a tender calf. Then he stood over them under the tree while they ate, a host waiting on his guests.
וַיִּקַּח חֶמְאָה וְחָלָב וּבֶן הַבָּקָר אֲשֶׁר עָשָׂה וַיִּתֵּן לִפְנֵיהֶם וְהוּא עֹמֵד עֲלֵיהֶם תַּחַת הָעֵץ וַיֹּאכֵלוּ׃
בראשית יח:ח
"He took butter and milk and the calf he had prepared, and set it before them. He stood over them under the tree, and they ate."
Bereishis 18:8
One of the guests promised that by this time next year Sarah would have a son. Sarah was listening just inside the tent door, and she laughed to herself.
וַיֹּאמֶר שׁוֹב אָשׁוּב אֵלֶיךָ כָּעֵת חַיָּה וְהִנֵּה בֵן לְשָׂרָה אִשְׁתֶּךָ וְשָׂרָה שֹׁמַעַת פֶּתַח הָאֹהֶל וְהוּא אַחֲרָיו׃ וַתִּצְחַק שָׂרָה בְּקִרְבָּהּ לֵאמֹר אַחֲרֵי בְלֹתִי הָיְתָה לִּי עֶדְנָה וַאדֹנִי זָקֵן׃
בראשית יח:י, יב
"He said, 'I will surely return to you at this time next year, and behold, Sarah your wife will have a son.' And Sarah was listening at the door of the tent, which was behind him. Sarah laughed to herself, saying, 'After I have grown old, will I have this delight? And my husband is old.'"
Bereishis 18:10, 12