Barukh Shem Kevod

This line, "Blessed be the name of the glory of His kingdom for ever and ever", is said immediately after the first verse of the Shema, the declaration of God's oneness that stands at the centre of Jewish prayer. Unlike the verses of the Shema themselves, which are drawn from the Torah, this response is not biblical, and the tradition preserves a striking custom around it: it is normally said in an undertone, a practice the Talmud explains through a story in which the patriarch Jacob's sons affirm their faith to him and he responds with these words, so that Israel says quietly what was first spoken privately, except on the Day of Atonement, when it is proclaimed aloud, as the angels are said to praise God. The line functions as a congregation's affirmation of God's kingship, appended to the confession of his unity, and its hushed recitation is one of the small, distinctive gestures of the daily liturgy.

Rabbinic legend explains the whisper this line is normally said in within the Shema through a story about Moses ascending to receive the Torah and overhearing the ministering angels praising God with these very words, blessed is the name of his glorious kingdom forever, borrowing the line for Israel's use but only on condition that it be said quietly, since it was not originally addressed to human ears. This aggadic account, recorded in classical rabbinic sources, is the traditional explanation for a practice, whispering, that the Mishnah already documents without offering the same story, Mishnah Yoma 3:8 recording that in the Jerusalem Temple the line was in fact said aloud by the assembled crowd whenever the high priest pronounced the divine name on Yom Kippur, the one context in which it was proclaimed rather than murmured.

That Temple era exception has left a trace in practice that survives the Temple's destruction: on Yom Kippur itself, many congregations today say barukh shem kevod aloud rather than in the customary whisper, a deliberate departure from the rest of the year's practice intended to recall the one day the line was spoken openly in Jerusalem. The line's placement immediately after the first verse of the Shema, rather than as part of the biblical text of the Shema itself, is itself evidence of separate origin, a liturgical insertion the rabbis positioned at the seam between two originally distinct textual units.