In modern traditional Judaism, pronouncing the four-letter name of God (יהוה) is taboo. Even during the reading of the Torah, this name is never pronounced as it is written in the text, but is replaced by the words "adonai" (Lord) or "elohim” (God, pl.); in daily speech, it replaced by word "ha-shem" (name), or pronounced by letters: "yud-hey-vav-hey" sometimes replacing “hey” with “key” so as not pronounce it exactly as it is written.
According to Jewish tradition, this ban was introduced during the time of the Second Jerusalem Temple after the death of the high priest Shimon ha-Tzadik in the III BC. Subsequently, this name could be pronounced only by the Jewish high priest only once a year - on the day of the Jewish holiday "Yom Kippur" (Day of Atonement), being alone in the sanctum sanctorum of the Jerusalem Temple. To this name was attributed such power, that there was a belief that if at the moment of its pronunciation the high priest would in some way unclean or dishonest before the people and God, he would die right there in the same moment; and since no one but only the high priest could enter there, a long rope was tied to his leg in order to pull out the corpse in case of his death.
Although there is no clear explanation of the Jewish etymology and meaning of this name, traditionally it is most often interpreted and translated as "who is", (Ex. 3:14), "he who is" or "he who was, is and will be." There is also no in Hebrew unambiguous version of its reading (possibly variations: Yahweh, Yahweh, Yahva, Yahweh, Yehva, Jehovah, etc.). Its true pronunciation was known only to the Jewish high priests, who didn't exist after the destruction of the Second Temple by the Romans in the I AD. Although, as Henry O. Thompson notes in "The Anchor Yale Bible Dictionary", "the pronunciation of יהוה as Yahweh is a scientific assumption", this transcription is now generally accepted and the most common.
Some researchers suggested that the Hebrew verbal root "יה" (yah, to be), from which the name Yahweh derives, was not Hebrew by its origin, but was adopted by the Jews in Egypt, where they lived for a long time, being in slavery, and from where they escaped under the leadership of Moses. In that time in Egypt was a lunar deity named Yah.
Another authors, such as, for example, B. G. Tilak and G. Prasad, see Vedic roots in the origin of the name of the God of Judaism, drawing obvious parallels with the name Yahva found in the Rig Veda, most often as an epithet of the fire god Agni. The following is the information given in Ganga Prasad's book "The fountainhead of religion".
In the Rig Veda, the name Yahva is found in hymns addressed to Agni, Indra, Soma, Ashvinas, Vishwadevas and Marudghans and literally means “restless, swift, active”, or in the meaning of “continuously moving or flowing” it can refer to mahat, the Universal Principle. In total, the name Yahva is mentioned in the Rig Veda 41 times and found in 33 of 1028 its hymns, with 21 masculine (yahva) and 20 feminine (yahvī) used. 16 hymns use masculine, 16 feminine, and only one hymn uses both at once.
The Sanskrit etymology of the word yahva is as follows: yah + hva, where yah = “that which moves, air (vayu)”, “fame” (Apte dictionary), and hva = roots hū and hvā - “to call, to invoke”. Traditionally, (in sanskrit) the etymology of "yahva" is derived from "yah". In Monier-Williams' dictionary, among others, are given such meanings of the word yahva as “a sacrificer” and “heaven and earth”.
The Nighantu also tells us that the word yaha means water (Nig. I. 12) or strength (Nig. II. 9); while the adjective yahva (Nig. III. 3; Nir. VIII, 8);. means "great". In this sense Yahva is applied in the Rigveda to Soma (Rv. IX. 75. i ), to Agni (Rv. III. i. 12) and to Indra. (Rv. VIII. 13. 24).
Yahva is one of the oldest names of Rudra, but in the Rig Veda it is more closely related to Agni (which is also associated with Rudra), whose vehicle is a ram or a goat. Here should be noted some parallels with Judaism - the sacrifice of the lamb, the appearance of God in the form of fire (a burning bush, a pillar of fire, etc.) and the previously existing significant fiery component of Jewish temple ritual practice. In the Rig Veda, the name Yahva is used 21 times as an epithet for Agni:
yahva - RV 10.110;
yahvaḥ - RV 3.1, 3.5, 4.5, 4.7, 4.58, 5.1, 7.6, 7.8, 9.75, 10.11;
yahvam - RV 1.36; 3.3; 4.5; 5.16; 8.13; 10.92;
yahvasya - RV 3.2 and 3.28.
This name do occur even in Zend Avesta - the Aryan Parsi scripture also. In “The Fountainhead of Religion: A Comparative Study of the Principle Religions” Ganga Prasad says: “It is not a little remarkable that this similarity extends even to the names of the Deity which occur in the Bible and the Zend Avesta. In the Hozmuzd Yashla of the Zend Avesta, Ahura Mazda enumerates twenty of his names. The first is Ahmi (Sanskrit Asmi) “I am." The last is Ahmi yad Ahmi (Sanskrit Asmi yad Asmi) “ I am that I am.” Both of these phrases are also the names of the Jahweh in the Bible: And God said unto Moses: "I AM THAT l AM" and he said: "Thus shalt thou say unto the children oi Israel: I AM hath sent me unto you.” The similarity in these names is too striking to be accidental.
Dr. Spiegei is of opinion (though Prof. Max Muller holds it doubtful), that the word Ahura (the principal name of the Deity in the Zend Avesta ) is identical in meaning with the word Jehoira. Ahura he (Dr. Spiegei ) says, as well as Ahu, means lord and must be traced back to the root ah, the Sanskrit as which means ‘ to be,' so that Ahura would signify the same as Jahweh, “he who is.”
It can be assumed that such a migration of names, symbols and ideas became possible through mixed marriages and trade relations between different cultures (Egyptian and Vedic, for example), as well as through the existing from 1350 to 1500 BC on the territory of modern Syria, Iraq and Turkey, the powerful kingdom of Mitanni, whose rulers used chariots, Sanskrit names and terms.