His day is coming (Joel 2:1)
He utters His voice before His army (Joel 2:11)
His day is great and awesome (Joel 2:11)
He is gracious & merciful, slow to anger & abounding in steadfast love (Joel 2:13)
He relents over disaster (Joel 2:13)
He is Jealous (Joel 2:18)
He has done great things (Joel 2:21)
He has dealt wondrously (Joel 2:26)
He is the LORD God and there is no one else (Joel 2:27)
He will pour His Spirit upon all flesh (Joel 2:28)
The LORD roars from Zion (Joel 3:16)
He utters His voice from Jerusalem (Joel 3:16)
The LORD is a refuge to His people (Joel 3:16)
He is a stronghold to Israel (Joel 3:16)
He dwells in Zion, His holy mountain (Joel 3:17)
While i admit that these are a mere surface level scratch at what Joel teaches about God, they each point our minds towards deeper contemplation about themselves.