Augustine very often urged his people to discover themselves in the Psalms, to recognize that the Psalmist’s voice was theirs, but on condition that their hearts, and their actions, were in harmony with the Psalmist’s voice. “Whose voice is this?” he asked once, and replied, “Yours, if you wish.”
“With those who hated peace I was peaceable” (Ps 119: 7). To hear the truth, beloved brothers and sisters, to be able to test the truth of what you’re singing, you have to begin to do what you are singing. However much I may say, however I may explain it, whatever the words I use, it enters the hearts only of people who are doing it. Start to act in this way, and you’ll see what we’re saying. Then tears flow with every word, then the Psalm is sung and the heart is doing what is being sung. How many people sing aloud but are silent in their hearts! And how many never speak with their lips, but their affections cry out! God’s ears listen to a person’s heart: just as the body’s ears listen to another’s mouth, so God’s ears listen to the heart. Many whose mouths are shut are being heard, while many shouting loudly aren’t being heard. We have to pray with our affections and say, “My soul has long been a sojourner. With those who hated peace I was peaceable.” (EnPs 119, 9; PL 37, 1604)
I wonder how many people understand that the Responsorial Psalm at Mass is supposed to be, or become, their response to the first reading. Perhaps we need to preach or instruct about this? Priests and deacons might think about preaching the Responsorial Psalm. I must admit I never think to do it myself.