1.The Ba'al Ha'turim says that we learn about the Birkat Kohanim from the blessings of Hashem to Avraham.

2. The three alters of Avraham represent the 3 temples. In this Sicha by the Lubavitcher rebbe, the concept of the "action of the forefathers is an indication for the children" as it applies to the Korbanot and the 3 Temples.