Jehovah’s Witnesses believe that use of the word Jehovah is essential for salvation.
“Walking in God’s name involves at least three things. First, we must proclaim that name to others, recognizing that only those who ‘call on the name of Jehovah will be saved.’ (Rom. 10:13)” Watchtower 2013 Mar 15 pp. 24-28 Honor Jehovah’s Great Name
This is flawed reasoning, as it is based on a mistranslation of Romans 10:13.
Jehovah in the New Testament shows that not a single ancient New Testament manuscript has been found containing the Tetragrammaton (YHWH). Inclusion of the word Jehovah in the New Testament of the New World Translation of the Holy Scriptures (NWT) is one of the most important errors in Watchtower theology.
Although YHWH appears almost 7,000 times in the Old Testament, it never has been found in any New Testament manuscripts. The Watchtower reasons that the word Jehovah was originally in the New Testament, but removed without trace. This undermines the integrity of the entire Bible. By adding the word “Jehovah” to the New Testament in the NWT, the Watchtower changes the meaning of key Christian Scriptures.
The exact pronunciation of the Tetragrammaton (YHWH) is unknown, but it is generally accepted to be Yahweh. Jehovah or Yahweh looks at the history of the word Jehovah and whether it should be used by the Watchtower.