(4) Give him a lamp in Jerusalem.--There is here a brief allusion to the victory recorded in the Chronicles, which obviously was the turning-point in the struggle, saving the "lamp" of the house of David from extinction, and "establishing" Jerusalem in security. "For David's sake" is, of course, for the fulfilment of the promise to David (2Samuel 7:12-16). In virtue of the continuity of human history, the Divine law always ordains that, in respect of consequences, the good deeds as well as the sins of fathers are "visited on their children."

Pulpit Commentary

Verse 4. - Nevertheless [נרךדנוס ,דךס ,תעב כִּי, Gesen. 393] for David's sake did the Lord his God give him a lamp [Better than margin, candle. The word is "always used figuratively of progeny." See note on ch. 2:26; and of 2 Samuel 21:17; Job 18:5, 6; Psalm 132:17] in Jerusalem, to set up his son after him, and to establish Jerusalem [But for David's piety, that is to say, his family would have been dethroned, if not destroyed, as was that of Jeroboam (1 Kings 14:10), of Baasha (1 Kings 16:2), of Ahab (2 Kings 10:11), etc. Abijah was the third prince of that line who had permitted idolatrous worship, so that that dynasty had richly deserved to forfeit its position. The stability of the family of David on the throne for nearly 400 years, amid all the changes and chances of that period, and whilst in Israel there were "nine changes of dynasty within 250 years" is, as Rawlinson remarks, very "difficult to account for on mere grounds of human reason"]:

Matthew Henry's Concise Commentary

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.

Gill's Exposition of the Entire Bible

Nevertheless, for David's sake did the Lord his God give him a lamp in Jerusalem,.... A kingdom there, as the Targum, splendid and glorious, to be continued in his posterity: to set up his son after him; in it:

and to establish Jerusalem: to continue that in which the temple was, for the sake of which, and the worship of God in it, there was a succession of David's posterity on the throne of Judah.

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