For David had lived an exemplary life before GOD all his days, not going off on his own in willful defiance of GOD's clear directions (except for that time with Uriah the Hittite).
Asa spared nothing and no one; he went so far as to remove Queen Maacah from her position because she had built a shockingly obscene memorial to the whore goddess Asherah. Asa tore it down and burned it up in the Kidron Valley.
Unfortunately, he didn't get rid of the local sex-and-religion shrines. But he was well-intentioned--his heart was in the right place, in tune with GOD.
Asa took all the silver and gold that was left in the treasuries of The Temple of GOD and the royal palace, gave it to his servants, and sent them to Ben-Hadad son of Tabrimmon, the son of Hezion king of Aram, who was ruling in Damascus, with this message:
"Let's make a treaty like the one between our fathers. I'm showing my good faith with this gift of silver and gold. Break your deal with Baasha king of Israel so he'll quit fighting against me."
Ben-Hadad went along with King Asa and sent out his troops against the towns of Israel. He attacked Ijon, Dan, Abel Beth Maacah, and the entire region of Kinnereth, including Naphtali.
Then King Asa issued orders to everyone in Judah--no exemptions--to haul away the logs and stones Baasha had used in the fortification of Ramah and use them to fortify Geba in Benjamin and Mizpah.
A full account of Asa's life, all the great things he did and the fortifications he constructed, is written in The Chronicles of the Kings of Judah. In his old age he developed severe gout.
Baasha son of Ahijah of the tribe of Issachar ganged up on him and attacked him at the Philistine town of Gibbethon while Nadab and the Israelites were doing battle there.
As soon as he was king he killed everyone in Jeroboam's family. There wasn't a living soul left to the name of Jeroboam; Baasha wiped them out totally, just as GOD's servant Ahijah of Shiloh had prophesied--