Note 18 — II. OUR DUTIES. (continued 3)

There are two forms of the blessing which accompanies the performance of a Divine precept: the precept is expressed (1) by a noun which is preceded by the preposition ‏עא‎ “concerning;” (2) by the infinitive of a verb preceded by the preposition ‏ל‎ “to,” e.g., “concerning the commandment of tsitsith,” and “to wrap ourselves with a garment provided with tsitsith.” The latter form is used (1) when the blessing is recited before the performance of the mitsvah has commenced; (2) when he who performs the mitsvah is personally commanded to perform it. In all other cases the first form is used. Hence ‏על מצות ציצת‎, because we are, as a rule, not in a fit state for prayer when we put it on, and therefore recite the blessing later on; ‏על מקרא מגלה‎; because he who reads might just as well be one of the listeners. We say ‏להניח תפלין‎ at the commencement of the mitsvah; ‏על מצות תפלין‎ before the second part. (See Babyl. Talm. Pesachim, p. 7.) ↑