Good question! Why do some Bibles write Jehovah & others write Yahweh for the Name of G-d? (To answer a question with a question is a very Jewish thing to do!)
In the beginning the L-rd's Name was well-known. When people called upon His Name, things happened! But people abused it. They called upon it in vain. When the ancient Rabbis wrote the Name in the Scriptures, they were concerned that the Name of the L-rd be handled with great respect, even to the point of washing their hands & praying before writing it. The L-rd Himself said, "You shall not use the Name of the L-rd your G-d in vain." Therefore, the rabbis used 4 Hebrew letters for the Name of G-d & added different vowels. Sometimes it is written with just two letters. It is called the unpronounceable Name of God, because it is not to be pronounced. Instead, in Hebrew, we substitute the word "HaShem" (the Name) for it. Or we say "Adonai" (My L-rd/Master). The Yemenite Jews substitute the word "HaMakom" (the Place) out of reverence for His Name.
In order to convey that same reverence in English, we write G-d, or L-rd.
The truth is, no one knows how to pronounce the Name anymore. But the story doesn't end there! The L-rd has not left us hanging.
He sent His Son and told us all to pray to the Father in the Name of His Son-- None other than Y'shua Himself. (John 16:24)
He also sent His Spirit to dwell in us and to glorify the Father & the Son through us. He said that we can approach HIM & call him Father & Abba (Daddy). How absolutely wonderful!!!! (Romans 8:14-15)
When John F. Kennedy was President of the United States, he was sitting in the Oval Office conducting important State business. His little son, John-John came running into the office and climbed up on the President's lap. Kennedy just laughed and told everyone, "He doesn't know that I'm the President. I'm just his father."
We have that kind of relationship with the G-d of the Universe. He always has time for us. Y'shua (the innocent One) paid the way for that relationship. He took the punishment that we (the Guilty) deserved, and the L-rd adopted us into His Family. We have become Children of the Living G-d! Access to the Throne Room is free & easy!
Thank you, L-rd, for loving us enough to die for us & for your resurrection power which helps us to live for You; help us NEVER to take that for granted & to ALWAYS treat You with the respect You so richly deserve!
Writing G-d & L-rd is a daily reminder of that respect.
Lura Maiman, Congregation Yeruel, Israel