וַיְסַפֵּ֥ר הָעֶ֖בֶד לְיִצְחָ֑ק אֵ֥ת כָּל־הַדְּבָרִ֖ים אֲשֶׁ֥ר עָשָֽׂה׃
종이 그 행한 일을 다 이삭에게 고하매
Rashi on Genesis
ויספר העבד AND THE SERVANT RELATED — He reported to him the miracles that had been wrought for him — how the earth had shrunk for him, and how Rebecca was ready for him in response to his prayer (Genesis Rabbah 60:15).
Rashbam on Genesis
ויספר העבד ליצחק, to inform him of all the miracles he had encountered on the way to carrying out his mission. This was to convince Yitzchok that Rivkah was destined for him from heaven.
Radak on Genesis
ויספר, Eliezer told Yitzchok all that happened to him since he had commenced his mission. He did so during the time it took to reach Avraham’s house after Yitzchok had met them. It is possible that they arrived in Chevron on that same day, or the day following.