The Hebrew name Yoel (Joel) means "YHWH is God" or "the LORD is God." It is a theophoric name combining Yo (a shortened form of YHWH) and El (God). The name is borne by several individuals in the Old Testament, most notably the prophet Joel, author of the book bearing his name.
The prophet Joel delivered one of the most powerful prophetic messages in Scripture, calling Israel to repentance and foretelling the outpouring of the Holy Spirit. His prophecy in Joel 2:28-32, quoted by Peter at Pentecost (Acts 2:16-21), bridges the Old and New Testaments. The name itself is a confession of faith — declaring that YHWH alone is the true God, echoing the same declaration Elijah made on Mount Carmel.