1 In this Psalm, the humility of one that is a servant of God and faithful is commended unto us, by whose voice it is sung; which is the whole body of Christ. For we have often warned you, beloved, that it ought not to be received as the voice of one man singing, but of all who are in Christ's Body. And since all are in His Body, as it were one man speaks: and he is one who also is many....Now he prays in the temple of God, who prays in the peace of the Church, in the unity of Christ's Body; which Body of Christ consists of many who believe in the whole world: and therefore he who prays in the temple, is heard. For he prays in the spirit and in truth, who prays in the peace of the Church; not in that temple, wherein was the figure....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)