Discusses the subject of  Tenaim in Mitzvos - contingencies in the performance of Mtzvos – when the actualization of the Mitzvah is dependent upon the fulfillment of a certain condition.

All Halachos of Tenaim are derived from the episode in Parshas Matos, where the B'nei Gad and Reuven request to settle in the territories on the other side of the Yarden.  The Torah describes how Moshe Rabbeinu stipulated to Bnei Gad and Reuven that he would grant their request, but only if they cross over the Yarden and fight with the rest of Klal Yisroel to conquer Eretz Yisroel. If they did not fulfill this condition, his agreement to this request would be retroactively nullified.

Chazal examined these Pesukim and based the laws and conditions of Tenaim on them.  While most Tenaim are related to acquisitions (i.e. kinyanim), we also utilize Tenaim in our daily Mitzvos – i.e. Davening, Sefiras Haomer, Tefillin, Shemini Atzeres, etc.  One requirement of performing a Mitzvah with a Tenai is that one is permitted to perform that Mitzvah through a Shaliach as well.  Any Mitzvah that cannot be performed through a Shaliach can also not be performed with a Tenai.  How then can we perform the mitzvos of Tefillin, Shema, Afikoman, etc. with a Tenai?

We examine the various reasons why a Mitzvah that is excluded from using a Shaliach is also excluded from having a Tenai.  This discussion leads to the solution of the above dilemma.  This sugya also has relevance to this week’s parsha, Parshas Pinchas, where all of the Moadim are discussed.