At one time, Moses asked the Lord what His name was. We read in Exodus 3:13-14, “And Moses said unto God, Behold, when I come unto the children of Israel, and shall say unto them, The God of your fathers hath sent me unto you; and they shall say to me, What is his name? what shall I say unto them? And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you.” When Moses asked the Lord for His name, he was really asking the Lord to describe Himself. The word ‘name’ properly means ‘memorial’ or a description of who the person is. So we see that the Lord really gave Moses a description of Himself rather than giving him a proper name. He spoke of His eternal existence   In fact, all the names that we find of the Lord given in His Word are descriptive of Him.

The Lord then goes on to say to Moses in verse 15, “And God said moreover unto Moses, Thus shalt thou say unto the children of Israel, The LORD God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath sent me unto you: this is my name for ever, and this is my memorial unto all generations.” “LORD God” is properly ‘Jehovah (Yahweh) Elohiym’. In the KJV, when you see the word LORD in all capital letters, that is JEHOVAH. This is the name given to us of the Lord since the creation of the world as we read in Genesis 2:4, “These are the generations of the heavens and of the earth when they were created, in the day that the LORD God made the earth and the heavens.”

There is nothing in the Pentateuch (Moses’ writings) to prevent the Jewish people from pronouncing any of the names of God. It became a custom among the Jews to use substitute Names for God. For example, instead of pronouncing the four-letter Name (YHVH), they would substitute the Name “Adonai.” It was their ancient practice to not utter the sacred name of God. Perhaps in humility before the Lord, they refused to pronounce His name. However, the scripture does not forbid it.

From the website: under the heading of Judaism 101, I read this interesting piece: Some people render the four-letter Name as “Jehovah,” but this pronunciation is particularly unlikely. The word “Jehovah” comes from the fact that ancient Jewish texts used to put the vowels of the Name “Adonai” (the usual substitute for YHVH) under the consonants of YHVH to remind people not to pronounce YHVH as written. A sixteenth century German Christian scribe, while transliterating the Bible into Latin for the Pope, wrote the Name out as it appeared in his texts, with the consonants of YHVH and the vowels of Adonai, and came up with the word JeHoVaH (“J” is pronounced “Y” in German), and the name stuck. (300.10)