In the book bearing his name, Joel says so little about matters other than his message that even the time of his prophecy can only be estimated ​ — about 820 B.C.E., nine years after Uzziah became king over Judah.
See on umbes aasta 820 e.m.a, üheksa aastat pärast Juuda kuninga Ussija trooniletulekut.