Rashi notes that, when Hashem instructed Moshe Rabbeinu to transfer his authority to Yehoshua by means of semichah, “leaning of hands”, the Almighty said, yadcha, “your hand” in the singular, implying one hand. Moshe, however, applied both hands, generously, like a vessel which is full and brimming over and filled him with his wisdom to become the nation’s next leader.
Horav Avraham Pam, zl, (cited by Rabbi Sholom Smith in a Vort from Rav Pam) explains that when we bless someone by placing both hands on his head, it is an indication that it is executed with love. It is not burdensome, an obligation which we are compelled to carry out. Two hands means the person, indeed, wishes to transmit fully the blessings which he is about to render.
If Hashem had instructed Moshe to use one hand, why did he use two hands? He was not adhering to Hashem’s instructions. Perhaps, we might suggest the following. The gematria, numerical equivalent, of ahavah is thirteen. Likewise, the numerical equivalent of echad, one, is also thirteen. Thus, when (as the Rosh Yeshivah suggests) Moshe used two hands to express his ahavah, he was actually (in a way) using one, since ahavah and echad had the same gematria: when there is love (two hands), it becomes one.
We might derive another important lesson. When a rebbe seeks to transmit his wisdom to his student seamlessly, it is best executed using the medium of “two hands” – love. Without the inherent love that (should) exist(s), the student might not receive the “complete package”.
