First, decisiveness shows up in the shacharit service where there is supposed to be no break between the conclusion of the shema section and the beginning of the amidah. The various kaddishim are normally transition markers between sections and the kaddish is absent between the shema and amidah. In fact, it is not permissible even to respond with an “amen” at the close of the final blessing in the shema section. So … what gives? The Bavli (Babylonian Talmud) teaches us that there should be no break between redemption (the subject of the close of the shema section) and the amidah (B’rakhot, 4b). In other words, we must be swift and decisive in our encounter with God after praising him for redemption.
Second, the Mishnah teaches us that, even if a snake were to begin to wrap itself around one’s leg, it would be forbidden for one to interrupt his prayer (B’rakhot, 5:1)! The amidah is not to be interrupted for any reason. When we decide to encounter God in prayer it is the only thing that matters in the moment.
Third, if one finds that he or she has not prayed the first blessing with kavanah (intention), he or she is mandated by halakha to repeat it. In other words, without decisive intentionality, the act of prayer is not fulfilled.
Finally, the tractate of Megillah goes through a long list enumerating and describing the blessings over the amidah. At the end of the list our sages determine that the true end of the amidah is … silence (B.Megillah, Ch. 2). The halakha is that one should be still and silent before God before moving on to the next stage of davening. The decision to stop and be silent before God is one that the siddur cannot make for us. We have to be conscious and willing to decide to be still and silent before our King.
All of this is helpful regarding the amidah, but one might ask how this helps our decisiveness generally. I would suggest that decisively engaging our Creator and Redeemer impacts our ability to be decisive in other aspects of our lives. Why? Because God is Lord over everything that comes into our lives anyway! Any decision we are forced to make, however challenging, is something by which God wants to empower us. May we all be more decisive in our relationship with God, particularly in the amidah. Clearer decision making in all areas is likely to follow.