Enough has been said to show that the superscriptions are later than the psalms themselves, and often, if not always, unreliable; we are therefore wholly dependent upon internal evidence, and the criteria for Davidic authorship must be sought outside the Psalter. The only absolutely undisputed poems of David's are the elegy over Saul and Jonathan in 2 Samuel i. and the lament over Abner (2 Sam. iii. 33, 34). There is no means of proving that 2 Samuel xxii. (=Ps. xviii.) and 2 Samuel xxiii. 1-7 are David's, as they are interpolated in a section of Samuel which is itself an interpolation (xxi.-xxiv.), interrupting as it does the continuity of 2 Samuel xx. and I Kings i. The data offered by the elegy are much too slender to enable us to decide whether any particular psalm is David's or not. Some have ventured to ascribe a dozen psalms or so to him on the strength of their peculiar vigour and originality, but obviously all such decisions must be altogether subjective. What is certain is that David was an accomplished musician (1 Sam. xvi. 18) and a great poet (2 Sam. i.), a man of the most varied experience, rich emotional nature and profound religious feeling, a devoted worshipper of Jehovah, and eager to build Him a temple; and it is not impossible that such a man may have written religious songs, but in the nature of the case it can never be proved that he wrote any of the songs in the Psalter. Psalm xviii. has been by many assigned to him with considerable confidence because of the support it is thought to receive from its appearance in a historical book; but besides the fact that this support, as we have seen, is slender, the psalm can hardly, at least in its present form, have come from David. The superscription assigns it to a later period in his life when he had been delivered from all his enemies; but at that time he could not have looked back over the past, stained by his great sin, with the complacency which marks the confession in vv. 20-24. Others have supposed that xxiv. 7-10, with its picture of the entrance of Jehovah through the "ancient gates," may well be his. It may be, if the gates are those of the city; but if, as is more probable, they are the temple gates, then the psalm must be long after the time of Solomon. In the quest for Davidic psalms we can never possibly rise above conjecture. Later ages regarded David as the father of sacred song, just as they regarded Moses as the author of Hebrew law.