כִּ֤י ׀ לֹא־תַחְפֹּ֣ץ זֶ֣בַח וְאֶתֵּ֑נָה ע֝וֹלָ֗ה לֹ֣א תִרְצֶֽה׃
因為你不喜愛祭物，不然我就獻上；燔祭你也不悅納。
Mishneh Torah, Prayer and the Priestly Blessing
Before reciting the first blessing in each of the services, one begins, "O Lord, open Thou my lips, and my mouth shall declare Thy praise," (Psalms 51:17) and after concluding the service, one adds, "Let the words of my mouth and the meditation of my heart be acceptable before Thee, O Lord, my Rock and my Redeemer," (Psalms 19:15), after which the worshipper steps backward.