Charles Ellicott Commentary Genesis 24:63

"And Isaac went out to meditate in the field at the eventide. And he lifted up his eyes, and saw, and, behold, there were camels coming." — Genesis 24:63 (ASV)

To meditate. —Many Jewish commentators translate to pray, and derive one of the three Jewish forms of prayer from this act of Isaac. But though the verb is rare, the substantive is used in Psalms 104:34 of religious meditation; and this sense well agrees with the whole character of the calm, peaceful Isaac, already marked out as the type of the Lamb dumb before His slayers (Genesis 22:7).