Joel 2:26, 32

Joel 2:26, 32 - "And ye ... shall praise the name of Jehovah your God .... And it shall come to pass, that whosoever shall call on the name of Jehovah shall be delivered." - ASV.

 "You WILL ... praise the name of Yahweh your God .... All who call on [`invoke' - REB] the name of Yahweh will be saved" - NJB.

Here, like knowing God (Jn 17:3; 2 Thess. 1:8, 9), calling on (or invoking) Jehovah's name is an essential part of the road that leads to life.

Since it is a requirement to call upon, or invoke the name Jehovah, the knowledge and use of that name IS essential (as made known in the OT at least)! And, like knowing God, "calling upon his name, Jehovah" includes much more than merely pronouncing his name aloud in prayer. But, nevertheless, it does include the knowledge and use of his personal name, Jehovah (or Yahweh).

For example, Elijah, in his famous demonstration of who the only true God is, told the priests of Baal, "Call on the name of your god, and I will call on the name of Jehovah: and the God that answers by fire, let him be God." So how did the priests of Baal call on the name of their god? "And they ... called on the name of Baal ... saying `O Baal, hear us.'" And how did Elijah call on the name of Jehovah? "O Jehovah .... Hear me, O Jehovah, hear me, that this people may know that thou, Jehovah, art God.... And when all the people saw it, they fell on their faces: and they said [aloud, uncoded, in plain language], `Jehovah, he is God'" - ASV, 1 Ki.18:24, 26, 36-39. - Obviously, calling on (or invoking) the name of Jehovah includes the reverent use of that only personal name of the true God!

Concerning Joel 2:32, also see
Joel 2:32 (JWQ&A)