Apparently the psalm falls into two halves, of which the former (vv. 1-16) seems to have been sung as a processional hymn while approaching the sanctuary, and the latter (vv. 17-29), partly at the Temple gates, partly by a chorus of priests within, and partly by the procession when it had entered. Every reader recognises traces of antiphonal singing; but it is difficult to separate the parts with certainty. A clue may possibly be found by noting that verses marked by the occurrence of "I," "me," and "my" are mingled with others more impersonal. The personified nation is clearly the speaker of the former class of verses, which tells a connected story of distress, deliverance, and grateful triumph; while the other less personal verses generalise the experience of the first speaker, and sustain substantially the part of the chorus in a Greek play. In the first part of the psalm we may suppose that a part of the procession sang the one and another portion the other series; while in the second part (vv. 17-29) the more personal verses were sung by the whole _cortège_ arrived at the Temple, and the more generalised other part was taken by a chorus of priests or Levites within the sanctuary. This distribution of verses is occasionally uncertain, but on the whole is clear, and aids the understanding of the psalm. First rings out from the full choir the summons to praise, which peculiarly belonged to the period of the Restoration (Ezra iii. 11; Psalms cvi. 1, cvii. 1). As in Psalm cxv., three classes are called on: the whole house of Israel, the priests, and "those who fear Jehovah"--_i.e._, aliens who have taken refuge beneath the wings of Israel's God. The threefold designation expresses the thrill of joy in the recovery of national life; the high estimate of the priesthood as the only remaining God-appointed order, now that the monarchy was swept away; and the growing desire to draw the nations into the community of God's people.