John Gill Commentary Ezekiel 1:2

"In the fifth [day] of the month, which was the fifth year of king Jehoiachin`s captivity," — Ezekiel 1:2 (ASV)

In the fifth [day] of the month
The month Tammuz, as before:

(which [was] the fifth year of Jehoiachin's captivity)
; the same with Jeconiah and Coniah, as he is sometimes called; he was taken by the king of Babylon, when he had reigned but three months, and his captivity held seven and thirty years, (2 Kings 24:8 2 Kings 24:12) (25:27) .