Yitzchak's Blessing

Rav Chanin said in the name of Rav (Nedarim 7b) : One who hears his fellow utter Hashem’s name in vain is obligated to excommunicate him; otherwise, he himself is fit to be excommunicated. The Gemora explains the rationale behind this: For wherever the unnecessary utterance of the Divine Name is prevalent, poverty will be prevalent, and poverty is regarded as death. (Thus we see the severity of Hashem’s Name being mentioned in vain.)

Using this Gemora, Reb Shlomo Kluger explains the following verse [Breishis 27:23]: And he did not recognize him because his hands were hairy like the hands of his brother Esav, and he blessed him.

What caused Yitzchak to bless him? What is the connection between the observation that his hands were hairy like Esav and the blessing?

He explains: Wherever the unnecessary utterance of the Divine Name is prevalent, poverty will be prevalent. Up until this moment, Esav did not regularly utter the Name of Hashem. Therefore, Yitzchak had no need to be concerned about Esav becoming poor. However, now that he heard “his hairy son” using the Name of Hashem, he decided that it was time to bless him.