He walked in all the sins of his father - Yet Abijam prepared precious offerings for the temple service 1 Kings 15:15, probably to replace vessels which Shishak had carried off, and in his war with Jeroboam professed himself a faithful servant of Yahweh 2 Chronicles 13:10-12.

His heart was not perfect - He was an idolater, or did not support the worship of the true God. This appears to be the general meaning of the heart not being perfect with God.

And he walked in all the sins of his father, which he had done before him,.... Having such bad examples as both parents to copy after; it chiefly respects idolatrous practices, see 1 Kings 14:23,

and his heart was not perfect with the Lord his God; he did profess the true God, and worshipped him, but not wholly, and only, and sincerely; he worshipped other gods besides him: and so his heart was not

as the heart of David his father; who was a sole and sincere worshipper of God, never departed from him and his service.

Abijam walked as king in the footsteps of his father. Although he made presents to the temple (1 Kings 15:15), his heart was not שׁלם, wholly or undividedly given to the Lord, like the heart of David (cf., 1 Kings 11:4); but (כּי, after a previous negative) for David's sake Jehovah had left him a light in Jerusalem, to set up his son after him and to let Jerusalem stand, because (אשׁר) David had done right in the eyes of God, etc., i.e., so that it was only for David's sake that Jehovah did not reject him, and allowed the throne to pass to his son. For the fact itself compare 1 Kings 11:13, 1 Kings 11:36; and for the words, "except in the matter of Uriah the Hittite," see 2 Samuel 11 and 12.

And he walked in all the sins of his father, which he had done before him: and his heart was not perfect with the LORD his God, as the heart of David his father.

3. his heart was not perfect with the Lord . , as the heart of David his father-(Compare 1Ki 11:4; 14:22). He was not positively bad at first, for it appears that he had done something to restore the pillaged treasures of the temple (1Ki 15:15). This phrase contains a comparative reference to David's heart. His doing that which was right in the eyes of the Lord (1Ki 15:5) is frequently used in speaking of the kings of Judah, and means only that they did or did not do that which, in the general course and tendency of their government, was acceptable to God. It furnishes no evidence as to the lawfulness or piety of one specific act.

15:1-8 Abijam's heart was not perfect with the Lord his God; he wanted sincerity; he began well, but he fell off, and walked in all the sins of his father, following his bad example, though he had seen the bad consequences of it. David's family was continued as a lamp in Jerusalem, to maintain the true worship of God there, when the light of Divine truth was extinguished in all other places. The Lord has still taken care of his cause, while those who ought to have been serviceable thereto have lived and perished in their sins. The Son of David will still continue a light to his church, to establish it in truth and righteousness to the end of time. There are two kinds of fulfilling the law, one legal, the other by the gospel. Legal is, when men do all things required in the law, and that by themselves. None ever thus fulfilled the law but Christ, and Adam before his fall. The gospel manner of fulfilling the law is, to believe in Christ who fulfilled the law for us, and to endeavour in the whole man to obey God in all his precepts. And this is accepted of God, as to all those that are in Christ. Thus David and others are said to fulfil the law.