The last day of Sukkos is Hoshana Rabba. The purpose and objective of Hoshana Rabba, is to receive a ‘Kiss’ from Hashem Yisborach! In fact, on this day which is the culmination of the beautiful journey of Rosh Hashana, Yom Kippur, Aseres Y’mei Teshuva and Sukkos itself, we reach an exalted level where we are one with Hashem.
In the Yehi Ratzon which we recite upon completing the Hoshanos, we mention and acknowledge this special (and reciprocal) ‘mouth kiss’ between us and Hashem Yisborach. The definition of a ‘mouth kiss’, is that it is entirely reciprocal. There is no way to avoid complete reciprocation under these conditions. If one party turns away from the other – even slightly, it cannot be considered a true mouth kiss, since the faces are not completely lined up with one another.
Therefore, a true ‘N’shikas Picha’ by definition, is where you give a kiss and receive a kiss at the very same time. (The Torah tells us that Moshe Rabbeinu merited a ‘Misas N’shika’ from Hakadosh Baruch Hu at the end of his life. This is the most exalted and beautiful way for a human being to depart from this Earth, by receiving a ‘kiss’ from Hashem.)
The significance of this Kiss to Hashem on Hoshana Rabba, is to ‘breathe’ our Neshama into Hashem (so to speak) as an illustration and display of our desire to sacrifice ourselves to his will.
Since this kiss is reciprocal in nature (as we explained), we receive a new/cleansed Neshama from our Hakadosh Baruch Hu in return, since indeed when we give a kiss, we receive one in return!
<Heard From Harav Shimshon Pincus Z”l>