Psalm 137 is a song of Zion expressing desire for God's holy city while in exile in the land of Babylon. In that sense, it is reminiscent of the opening of the songs of ascents in Psalm 120, where the desire is to be delivered from a hostile foreign environment to travel to Jerusalem, as expressed in other songs of ascents, to be in fellowship with God. "Here [in Psalm 137] speaks the same deep love of Zion as that found in Psalms 42-43; 46; 48; 84; 122; 126 [these latter two being songs of ascents]. The editors of the Psalter attached this song to the Great Hallel as a closing expression of supreme devotion to the city at the center of Israel 's worship of the Lord" (Zondervan NIV Study Bible, note on Psalm 137). This psalm is earlier harmonized with the biblical narratives of the Babylonian Exile and prophecies delivered at that time. We now read it again in the context of the Psalter's arrangement. 

Psalm 137, which is not attributed to a particular author, appears to have been composed during the Babylonian exile. Even if it was written afterward, it nonetheless sums up the feelings of many of the Jews in captivity. It is a deeply mournful song, full of longing for their homeland, where they had some semblance of contact with God through His holy city and temple. Now they are far away, adrift, without mooring. They could no longer sing the joyful songs of past days. They "hung up their harps" on the trees--that is, they put away their musical instruments.

The Babylonians, however, asked for some music. While they may have actually wanted to hear some rousing hymns from the famed Jerusalem temple, it is also possible that this was simply a taunt--as in, "Let's hear some victory songs now...ha, ha." Whatever the case, in reflecting on the psalms of past days, recalling the former glory of their nation, all the Jews could do was sit by the great rivers of Babylon and weep. "How shall we sing the LORD's song in a foreign land?" they groaned (verse 4). How could they sing praises to God for His help and deliverance against enemies when their nation and temple lay in ruins and they themselves were captives? Would not this just be more reason for their captors to mock? And were they, unclean sinners banished from God's land, even worthy to sing His songs?

In any case, the psalmist, speaking for the nation, resolves to keep Jerusalem in the forefront of his mind--to never forget and to never cease hoping for restoration. Were the harps retrieved from where they were hung to sing at least this particular song? There is, of course, no way to know. But the sentiment was surely widespread.

In thinking of what had befallen their homeland, the utter horror and misery of what had occurred, there was no way to avoid recalling those who had carried out the destruction--the Babylonians. Moreover, they were urged on by the longtime foe of God's people, Edom. A special plea is made to God in verse 7 to keep in mind Edom's cruel enmity. And a pronouncement is then made against the Babylonians--that God will bring back on their heads what they have done to the Jews. It may well be that when the Babylonians asked for a song of Zion from the exiles, this very one was composed in response. It would have served as a rather shocking rebuke against any mocking and ridicule.

Today many grimace at the ending of this psalm, wondering how it squares with God's loving character. This is due to a misunderstanding of the wording here and of God's plan in general. First of all, the "one" who is "happy" at destroying the Babylonians in verses 8-9 is not specifically declared to be God. It may simply mean the national power that would later overthrow Babylon--the Persian Empire. The verses would then seem to constitute a prophetic declaration rather than an appeal. In fact, it seems likely that there is even a dual prophetic application here--to ancient Babylon as well as its end-time counterpart, the phrase "daughter of Babylon " perhaps hinting at this. Edom and Babylon will both play similar roles in the overthrow of Israel and Judah in the last days--and they will both suffer subsequent destruction themselves as repayment.

Of course, it is entirely possible that God is meant as the one repaying Babylon with destruction. If so, His being "happy" at doing so would not mean He sadistically relishes punishing human beings. The terminology in that case would have to be understood as His receiving "satisfaction" in a legal sense--that is, God's righteous justice being satisfied through just recompense. Babylon's "little ones" or "children," who are to be dashed against the rock, would in this case most likely mean Babylon's citizenry in general (the city or empire being portrayed as a woman, as already noted).

Moreover, being dashed against a rock is likely a figurative, rather than literal, expression denoting destruction. As the book Hard Sayings of the Bible notes on these verses: "One thing Babylon was devoid of was rocks or rocky cliffs against which anything could be dashed. In fact there were not any stones available for building, contrary to the rocky terrain of most of Palestine. All building had to depend on the production of sun-dried mud bricks and the use of bituminous pitch for mortar. Therefore when the psalmist speaks of 'dashing...against the rocks,' he is speaking figuratively and metaphorically" (Walter Kaiser Jr., Peter Davids, F.F. Bruce, Manfred Brauch, 1996, pp. 281-282).

Interestingly, "the verb [translated "dashes"] in its Greek form is found only in Psalm 137:9 (in the Septuagint, the Greek translation of the Hebrew text) and in the lament of our Lord over Jerusalem in Luke 19:44" (p. 281). In this verse Christ speaks to Jerusalem as if she is a mother, saying, "They [enemies] will dash you to the ground, you and the children within your walls." Again, children appear to denote the citizenry in general.

Of course, infants would die too--in both Babylon and Jerusalem . Yet all, children as well as adults, will be raised in the second resurrection to be taught God's ways and given the opportunity for lasting repentance, as explained in the Beyond Today Bible Commentary on Ezekiel 37. Indeed, repentance and conformity with His will, resulting in great blessing, is what God desires--what makes Him truly happy. He assures us in other scriptures that He takes no pleasure in punishing people for sin, but that they would turn and live. This passage is no exception.