Adam Clarke's Bible Commentary Verse 4. There is a river, the streams whereof ] The Chaldee understands the river, and its streams or divisions, as pointing out various peoples who should be converted to the faith and thus make glad the city of God, Jerusalem by their flowing together to the worship of the true God.
But the river may refer to the vast Medo-Persian army and its divisions: those branches which took Babylon; and, instead of ruining and destroying the poor Jews, preserved them alive, and gave them their liberty; and thus the city of God, and the tabernacle of the Most High, were gladdened.
Matthew Henry Commentary
Verses 1-5 - This psalm encourages to hope and trust in God; in his power an providence, and his gracious presence with his church in the worst of times. We may apply it to spiritual enemies, and the encouragement we have that, through Christ, we shall be conquerors over them. He is Help, a present Help, a Help found, one whom we have found to be so; Help at hand, one that is always near; we cannot desire a better, no shall we ever find the like in any creature. Let those be troubled a the troubling of the waters, who build their confidence on a floatin foundation; but let not those be alarmed who are led to the Rock, an there find firm footing. Here is joy to the church, even in sorrowfu times. The river alludes to the graces and consolations of the Holy Spirit, which flow through every part of the church, and through God' sacred ordinances, gladdening the heart of every believer. It is promised that the church shall not be moved. If God be in our hearts by his word dwelling richly in us, we shall be established, we shall be helped; let us trust and not be afraid.
Original Hebrew נהר5104 פלגיו6388 ישׂמחו8055 עיר5892 אלהים430 קדשׁ6918 משׁכני4908 עליון׃5945