C. F. Keil and Franz Delitzsch on Psalms 130:1

De Profundis

Luther, being once asked which were the best Psalms, replied, Psalmi Paulini; and when his companions at table pressed him to say which these were, he answered: Psa 32:1-11; Ps 51; Psa 130:1-8, and Psa 143:1-12. In fact in Psa 130:1-8 the condemnability of the natural man, the freeness of mercy, and the spiritual nature of redemption are expressed in a manner thoroughly Pauline. It is the sixth among the seven Psalmi poenitentiales (Psa 6:1-10, Psa 32:1-11, Ps 38, Ps 51, Ps 102, Psa 130:1-8, Psa 143:1-12).

Even the chronicler had this Psalm before him in the present classification, which puts it near to Ps 132; ; for the independent addition with which he enriches Solomon’s prayer at the dedication of the Temple, 2Ch 6:40-42, is compiled out of passages of Psa 130:1-8 (Psa 130:2, cf. the divine response, 2Ch 7:15) and Ps 132 (Psa 132:8, Psa 132:16, Psa 132:10).

The mutual relation of Psa 130:1-8 to Ps 86 has been already noticed there. The two Psalms are first attempts at adding a third, Adonajic style to the Jehovic and Elohimic Psalm-style. There Adonaj is repeated seven times, and three times in this Psalm. There are also other indications that the writer of Psa 130:1-8 was acquainted with that Ps 86 (compare Psa 130:2, שׁמעה בקולי, with Psa 86:6, והקשׁיבה בּקול; Psa 130:2, לקול תּחנוּני, with Psa 86:6, בּקול תּחנוּנותי; Psa 130:4, עמּך הסּליחה, with Psa 86:5, וסלּח; Psa 130:8, החסד עם ה/ הח, with Psa 86:5, Psa 86:15, רב־חסד). The fact that קשּׁוּב (after the form שׁכּוּל), occurs besides only in those dependent passages of the chronicler, and קשּׁב only in Neh 1:6, Neh 1:11, as סליחה besides only in Dan 9:9; Neh 9:17, brings our Psalm down into a later period of the language; and moreover Ps 86 is not Davidic.