A major transformation in Israelite Name theology, however, occurred in the Second Temple period between the conclusion of the Hebrew Bible and the age of Jesus. Restrictions on the ritual writing and pronunciation of the name YHWH had developed by at least the third century before Christ. In place of actually pronouncing the name YHWH when reading scriptures or praying, Jews increasing said ădōnāy in Hebrew, translated as kurios in Greek, both meaning simply "lord." (Hence the English use of LORD to render the divine name.)

In the Hebrew biblical manuscripts from this period they often wrote the name of God in the Paleo-Hebrew script indicating its special status and unique pronunciation. By the time of Jesus many Jews also began to simply say ha-šēm ("the Name" [of God]) when they came across the name YHWH in reading a text. This practice can already be found in Leviticus 24:11, 16 where an Israelite is described as blaspheming "the Name" (ha-šēm), meaning the name YHWH. These practices still continue among Orthodox Jews today, who, when reading aloud or speaking the name YHWH, will say ădōnāy (lord), ha-šēm (the name), or vocally spell the name, saying yôd-hê-vāv-hê.

These practices derived in large part from contemporary interpretations of the biblical prohibition against "taking the name of YHWH your God in vain" (Ex. 20:7; Dt. 5:11). Based on the Jewish tendency to "make a hedge for the Law"—which is to say, interpret the Law in the broadest sense possible to prevent one from even coming close to breaking a commandment—Jews increasing refused to say God's name at all. The transformed nature of this prohibition is most clearly reflected in the Greek translation of Leviticus 24:11-16. The Hebrew text reads: "whoever blasphemes/slanders the name of YHWH shall surely be put to death" (Lev. 24:16). But the Greek Septuagint, reflecting Jewish beliefs and practices in the second century B.C., reads: "whoever names the name (onomazōn de to onoma) of the Lord (kurios)—by death let him be put to death." In other words an original prohibition against misusing the name YHWH was transformed by at least the second century B.C. into a prohibition against even pronouncing the name at all.

There were two exceptions to this general prohibition. The first, and most important, was the pronunciation of the name YHWH by the High Priest at the temple on the Day of Atonement. The biblical text of the Day of Atonement ritual in Leviticus 16 does not mention a specific benediction to be said in the name of YHWH. Our information on the ritual pronunciation of the Name on the Day of Atonement comes from the Mishnah, a collection of rabbinic oral traditions recorded around A.D. 200.

When the priest and the people which stood in the Temple Court [on the Day of Atonement] heard the Expressed Name [YHWH] come from the mouth of the High Priest, they used to kneel and bow themselves and fall down on their faces (Mishnah, Yoma 6.2, 3.8, 4.2).

The book of the Wisdom of Sirach contains a detailed description of the Day of Atonement ritual performed by the High Priest Simon II, the Just (219-196 B.C.) (Sirach 50), and also mentions the people prostrating themselves at the mention of the Name (Sirach 50:20-21), just as described in the Mishnah. The Talmud records a tradition that after the death of Simon, people ceased to speak the Name aloud.