When I did my chaplaincy training years ago, one of the most striking differences I encountered between myself and my Christian colleagues was the ease and frequency with which they uttered "spontaneous" prayers and blessings. My sense is that as more rabbis go through chaplaincy training, this skill is gaining in popularity. In my own work, I have found that there are situations where it is both appropriate and powerful. Still, I continue to ponder the relative merits of spontaneous versus established blessings. In the biblical Book of Numbers, set in the wilderness, we encounter instructions for the Israelite priests on what to say when blessing the people. The words of this brief blessing, considered by scholars to be extremely ancient, are beloved in both Jewish and Christian contexts to this day: May God bless you and guard you. May God shine God's face upon you and be gracious to you. May God lift up God's face toward you and grant you peace. Rabbinic commentato...