וַיַּשְׁכֵּ֨ם אַבְרָהָ֜ם בַּבֹּ֗קֶר וַֽיַּחֲבֹשׁ֙ אֶת־חֲמֹר֔וֹ וַיִּקַּ֞ח אֶת־שְׁנֵ֤י נְעָרָיו֙ אִתּ֔וֹ וְאֵ֖ת יִצְחָ֣ק בְּנ֑וֹ וַיְבַקַּע֙ עֲצֵ֣י עֹלָ֔ה וַיָּ֣קָם וַיֵּ֔לֶךְ אֶל־הַמָּק֖וֹם אֲשֶׁר־אָֽמַר־ל֥וֹ הָאֱלֹהִֽים׃
And Abraham rose early in the morning, and saddled his ass, and took two of his young men with him, and Isaac his son; and he cleaved the wood for the burnt-offering, and rose up, and went unto the place of which God had told him.
Rashi on Genesis
וישכם AND HE ROSE EARLY — He was alert to fulfil the command (Pesachim 4a)
Ramban on Genesis
AND HE CLEAVED THE WOOD FOR THE BURNT-OFFERING. This illustrates Abraham’s zeal in performing a commandment for he thought that perhaps there would be no wood in that place, and so he carried it for three days. It may be that Abraham disqualified for use as an offering any wood in which a worm is found, as is the law of the Torah,381Midoth 2:5. and so he took from his house sound wood for the burnt-offering. Hence it says, And he cleaved the wood for the burnt-offering.