Comentario citado sobre Génesis 12:9

ויעל אברם וגו' הנגבה AND ABRAM WENT UP [OUT OF EGYPT] …TOWARDS THE NEGEB — He went up to proceed to the Southern part of the land of Israel — as it is said above (Genesis 12:9) “going on more and more to the Negeb” — to the Mount Moriah. Still, when one goes from Egypt to the land of Canaan, one proceeds from South to North, because Egypt is to the South of the land of Israel, as may be proved from the account of the journeys that the Israelites made in the wilderness and from the description of the boundaries of the land of Israel (see Numbers 33 and Numbers 34).

אם השמאל ואימינה ואם הימין ואשמאילה, what he meant was “if you will move north I will be south of you, whereas if you move south, I will be north of you, in the very location that I am now, which was in the south of the country as we know from 12,9 and 13,3.

והכבד את לבו HE ALLOWED HIS HEART TO BE HARDENED — The word הַכְבֵּד expresses doing something (the Hebrew infinitive but having a past meaning) just as, (Genesis 12:9) “going (הלוך) and journeying (ונסוע)”. So, too, (2 Kings 3:24) “and smiting (והכת) Moab”; (I Samuel 22:13) “and enquiring (ושאול) of God for him”; (1 Kings 20:37); “smiting (הכה) and wounding (ופצוע)”.

טחון — This is a present tense of continuous action like הלוך וכלות “going on destroying”; moulant in O. F. English grinding (cf. Rashi on Deuteronomy 3:6).