Commentary on the Bible, by Adam Clarke, [1831], at sacred-texts.com
An exhortation to give thanks to God for various mercies granted to all men, Psa 136:1-9; particularly to the Israelites in Egypt, Psa 136:10-12; at the Red Sea, Psa 136:13-15; in the wilderness, Psa 136:16-20; and in the promised land, Psa 136:21, Psa 136:22; for the redemption of the captives from Babylon Psa 136:23, Psa 136:24; and for his providential mercies to all, Psa 136:25, Psa 136:26.
This Psalm is little else than a repetition of the preceding, with the burden, כי לעולם חסדו ki leolam chasdo, "because his mercy endureth for ever," at the end of every verse. See below. It seems to have been a responsive song: the first part of the verse sung by the Levites, the burden by the people. It has no title in the Hebrew, nor in any of the Versions. It was doubtless written after the captivity. The author is unknown.
O give thanks unto the Lord: for he is good - This sentiment often occurs: the goodness of the Divine nature, both as a ground of confidence and of thanksgiving.
For his mercy endureth for ever - These words, which are the burden of every verse, כי לעולם חסדו ki leolam chasdo, might be translated: "For his tender mercy is to the coming age:" meaning, probably, if the Psalm be prophetic, that peculiar display of his compassion, the redemption of the world by the Lord Jesus. These very words were prescribed by David as an acknowledgment, to be used continually in the Divine worship, see Ch1 16:41 : also by Solomon, Ch2 7:3, Ch2 7:6, and observed by Jehoshaphat, Ch2 20:21; all acknowledging that, however rich in mercy God was to them, the most extensive displays of his goodness were reserved for the age to come; see Pe1 1:10-12 : "Of which salvation the prophets have inquired, and searched diligently, who prophesied of the grace that should come unto you, - unto whom it was revealed, that not unto themselves, but unto us, they did minister the things which are now reported unto you by them that preached the Gospel unto you by the power of the Holy Ghost sent down from heaven," etc.
The God of gods - לאדני האדנים ladonai haadonim. As adonai signifies director, etc., it may apply here, not to idols, for God is not their god; but to the priests and spiritual rulers; as Lord of lords may apply to kings and magistrates, etc. He is God and ruler over all the rulers of the earth, whether in things sacred or civil.
Who alone doeth great wonders - Miracles. No power but that which is almighty can work miracles, נפלאות niphlaoth, the inversion, or suspension, or destruction of the laws of nature.
By wisdom made the heavens - In the contrivance of the celestial bodies, in their relations, connexions, influences on each other, revolutions, etc., the wisdom of God particularly appears.
Stretched out the earth above the waters - Or, upon the waters. This seems to refer to a central abyss of waters, the existence of which has not been yet disproved.
Great lights - See the notes on the parallel passages in Gen 1:1, etc.
Smote Egypt in their first-born - This was one of the heaviest of strokes: a great part of the rising generation was cut off; few but old persons and children left remaining.
Divided the Red Sea into parts - Some of the Jews have imagined that God made twelve paths through the Red Sea, that each tribe might have a distinct passage. Many of the fathers were of the same opinion; but is this very likely?
Which led his people through the wilderness - It was an astonishing miracle of God to support so many hundreds of thousands of people in a wilderness totally deprived of all necessaries for the life of man, and that for the space of forty years.
Who remembered us in our low estate - He has done much for our forefathers; and he has done much for us, in delivering us, when we had no helper, from our long captivity in Babylon.
Giveth food to all flesh - By whose universal providence every intellectual and animal being is supported and preserved. The appointing every living thing food, and that sort of food which is suited to its nature, (and the nature and habits of animals are endlessly diversified), is an overwhelming proof of the wondrous providence, wisdom, and goodness of God.
The Vulgate, Arabic, and Anglo-Saxon, add a twenty-seventh verse, by repeating here Psa 136:3 very unnecessarily.