Musar zu Bereschit 26:2

All these three gifts are directly related to the patriarchs. The gift of Torah commenced during the lifetime of Abraham, as we know from Sanhedrin 97, in which the 6000 years designated for the history of man in this world are divided into 2000 years of Tohu, followed by 2000 years of Torah. This latter period began when the Torah reports both Abraham and Sarah as having converted people to belief in monotheism in Genesis 12,5: ואת הנפש אשר עשו בחרן. The gift of ארץ ישראל began to be real when Isaac was forbidden to leave that country even during periods of famine, and G–d explained that this was because this land was given to him and his descendants (Genesis 26,2-3).