“יִהְיוּ לְרָצוֹן אִמְרֵי-פִי, וְהֶגְיוֹן לִבִּי לְפָנֶיךָ, ה', צוּרִי וְגֹאֲלִי.” (תהילים י"ט:ט"ו)
“May the words of my mouth and the thoughts of my heart be acceptable before You, God — my Rock and my Redeemer.” (Psalms 19:15)
We add this verse at the end of the Amidah, the central prayer recited three times a day.
Initially, however, the Sages were not sure — does this verse belong before the Amidah, or after it? Should it be recited beforehand, so that it refers to the words of prayer about to be said? Or should it be recited after the Amidah, thus referring to the prayer previously recited?
The meaning of this request — “May the words of my mouth... be acceptable” — depends on this very question.
If recited at the start of the Amidah prayer, then it refers to the prayer about to be said. It expresses our desire that the prayers which follow will engage the soul and uplift the heart. We hope that we will succeed in directing our prayers with deep kavanah. It is a prayer for a powerful, uplifting Amidah.
If, on the other hand, the verse belongs at the end of the Amidah, then it refers to the result of our prayer experience.
Twelfth-century philosopher Rabbi Yehudah HaLevi explained in his classic work, The Kuzari, that each prayer is meant to uplift and refine our lives. Over time, it is inevitable that we become involved in mundane matters, and the impact of our previous prayer weakens. This continues until the time comes for the next prayer, when we rekindle the light of the soul. Spiritual life is thus a constant, cyclic pattern, with gradual descents halted by rapid climbs of spiritual ascent through prayer.
Thus, when recited after the Amidah, the request of “May the words of my mouth ... be acceptable” reflects our desire that the Amidah should enlighten our lives even after we have finished praying. The soul’s outpouring in prayer should not be limited to the hour of prayer, but serve as a practical tool to sanctify life.
How did the Sages resolve this question? They noted that this verse is located in the nineteenth psalm, after eighteen chapters of prayer. So too, the proper place for this verse is at the end of Amidah, after its Shemoneh Esrei (eighteen) blessings.
This insight reveals the primary benefit and purpose of prayer. More important than one’s spiritual elevation while praying is the practical impact that prayer should have on our lives. We can now understand the connection of prayer to the number eighteen — corresponding to the Gematria of the letters ח"י (chai), meaning ‘life.’ This is the message of this verse — urging us to elevate our lives to match the lofty feelings of holiness and closeness to God that we experienced during the hour of prayer.
(Adapted from Ein Eyah vol. I, p. 47 on Berakhot 9b)