Augustine. Exposition on the Book of Psalms. Schaff, Philip (editor). New York: Christian Literature Publishing Co, 1886. Nicene and Post-Nicene Church Fathers: Series 1: Volume VIII. Re-published 2014, Catholic Way Publishing. Kindle electronic edition, ISBN-13: 978-1-78379-372-3.
Augustine prefaces his remarks on Psalm 129 with the observation that although it is short it is very powerful. In verse one, the conflict is introduced, that some have striven against the Psalmist. Augustine notes that this is common in the Church, that there are many opponents (Augustine Psalms, loc. 340830, par. 2). He notes numerous points in the Old Testament where the testimony of God and the line of God's chosen people seems to exist in just one person. In verse two, then, Israel, taken by Augustine as the Church, says the opposition has not brought defeat (Augustine Psalms, loc. 340845, par. 3).
Augustine takes the statement of verse three to denote sinners settling and building their lives in the world of the church, though many modern translations would suggest a forceful and painful persecution (Augustine Psalms, loc. 340850, par. 4). Of concern to Augustine is the failure of the Church to censure evil. That failure allows evil to be excused and to be portrayed as good (Augustine Psalms, loc. 340855, par. 5). Augustine goes on to speak against clergy engaging in money lending for interest, as it draws God's people away from God's Word (Augustine Psalms, loc. 340865, par. 6).
Verse four then speaks of God as the one who works vengeance. It is the lofty, upraised necks of the proud which are presented to God for his wrath (Augustine Psalms, loc. 340870, par. 7). In contrast, the humble call out to God for mercy. This sets the humble apart from those who hate the Church (verse 5). Verse six compares the proud to grass which grows on a housetop. Augustine notes that such grass has no root or depth of soil, so it cannot prevail (Augustine Psalms, loc. 340879, par. 9). Verse seven confirms the futility of trying to reap such a crop.
Counter to the proud, in verse eight, God's people are greeted with the blessing of the Lord, as was the custom among Jews (Augustine Psalms, loc. 340889, par. 10). Augustine sees it as right within the Church to bless one another as well, particularly since all real blessing comes from God.