וַיֹּאכְל֣וּ וַיִּשְׁתּ֗וּ ה֛וּא וְהָאֲנָשִׁ֥ים אֲשֶׁר־עִמּ֖וֹ וַיָּלִ֑ינוּ וַיָּק֣וּמוּ בַבֹּ֔קֶר וַיֹּ֖אמֶר שַׁלְּחֻ֥נִי לַֽאדֹנִֽי׃
Y comieron y bebieron él y los varones que venían con él, y durmieron; y levantándose de mañana, dijo: Enviadme á mi señor.
Rashi
וילינו AND LODGED OVER NIGHT — wherever the root לין occurs in Scripture it signifies staying for only one night.
Radak
ויאכלו, this has been explained, i.e. now that Eliezer had explained his mission he felt free to eat the meal which had been placed before him.