Toldos

WHO, WHERE,  IS THE ONE WHO TRAPPED GAME AND BROUGHT IT TO ME, AND I ATE OF ALL BEFORE YOU CAME AND BLESSED HIM?  INDEED HE SHALL BE BLESSED (Bereshis 27:33).

Why did Yitzchak confirm the blessing given to Yaakov upon discovering it was obtained deceitfully?

Yitzchak realized that if he can be fooled by Yaakov he could be fooled by Esav as well.  If Yaakov can masquerade as an Esav, than Esav can masquerade as a Yaakov i.e. a righteous man. Yitzchak realized now that his positive estimation of Esav was a sham. Rivka's scheme was intended to drive home this point (Rav SR Hirsch).

Yitzchak knew by holy spirit that his blessing indeed rested upon the son who received the blessing- now understood to be Yaakov.  It is simply a reality that Yaakov is now blessed.  Holy spirit indicates the blessing took effect, showing that the right thing was done (Ramban).

This whole event involved so many remarkable coincidences that Yitzchak knew Yaakov has been selected by Divine Providence to receive the blessing (Malbim).

Chayeh Sara

Vayera

AFTER THESE THINGS G-D TESTED AVRAHAM AND SAID TO HIM "AVRAHAM" AND HE SAID "HERE I AM."...G-D'S ANGEL CALLED TO HIM FROM HEAVEN AND SAID "AVRAHAM, AVRAHAM" (22:1,11)

Why did G-d call Avraham's name once but the angel called him twice?

The angel was expressing special endearment as Avraham had just passed the most difficult test of his life: he obeyed G-d by his willingness to sacrifice his son.  Also, Avraham was preoccupied with a mitzva (offering Yitzchak) when the angel spoke to him, which was not the case when G-d spoke to Avraham.  Avraham was called twice to get his full attention (Kli Yakar).