For I know that Jehovah is great We have here a general description of the power of God, to show the Israelites that the God they worshipped was the same who made the world, and rules over all according to his will, neither is there any other besides him. He would not exclude others when he speaks of having known himself the greatness of God, but is rather to be considered as taking occasion from his own experience to stir up men generally to attend to this subject, and awake to the recognition of what lies abundantly open to observation. The immensity of God is what none can comprehend; still his glory, so far as was seen fit, has been sufficiently manifested to leave all the world without excuse for ignorance. How can one who has enjoyed a sight of the heavens and of the earth shut his eyes so as to overlook the Author of them without sin of the deepest dye? It is with the view, then, of stirring us up more effectually, -- that the Psalmist makes reference to himself in inviting us to the knowledge of God's glory; or rather he reprehends our carelessness in not being alive enough to the consideration of it. The second part of the verse makes the truth of the observation which I have already stated still more apparent, -- that the Psalmist's design was to retain the Israelites in the service and fear of the one true God, by a declaration to the effect that the God who covenanted with their Fathers was the same who created heaven and earth, No sooner had he made mention of Jehovah than he adds his being the God of Israel. It follows as a necessary consequence, that all who depart from this God prefer a god who has no claim to the title, and that Jews and Turks, for example, in our own day, are guilty of mere trifling when they pretend to worship God the Creator of the world. Where persons have diverged from the law and from the gospel, any show of piety they may have amounts to a renunciation of the true God. The Psalmist had, therefore, in his eye when he clothed God with a specific title,, to limit the Israelites to that.God who was set forth in the doctrine of the Law. If by 'lhym, Elohim, we understand the false gods of the Gentiles -- the title is given them only by concession, for it could not be properly assigned to what are mere lying' vanities; and the meaning is, that God's greatness altogether eclipses any pretended deity. But the expression would seem to include the angels, as has been already observed, in whom there is some reflection of divinity, as being heavenly principalities and powers, but who are exalted by God, and assigned such a subordinate place as may not interfere with his glory.

For I know - I, as the representative of Israel, and speaking in the, name of the people. This is said as the foundation or the reason for praise. It was the thorough conviction of the psalmist that God was great above all who were claimed to be gods, and that he only was worthy of worship.
That the Lord is great - See the notes at Psalm 95:3.
And that our Lord is above all gods - All that are worshipped as gods.

The Lord is great - Unlimited in his power: another reason.
Is above all gods - Every class of being, whether idolized or not; because he is the Fountain of existence. This is a fifth reason.

For I know that the Lord is great,.... Jehovah the Father is great in his perfections; in his power, wisdom, faithfulness, grace, and goodness; and in his works of creation, providence, and grace: and so is Jehovah the Son, who seems chiefly designed, who is called "our Lord" or "Adon" in the next clause; he is great, having the same perfections his Father has; and doing the same works, besides the miracles he wrought here on earth, and the great work of our redemption: he is the great God and our Saviour, and a great Saviour he is; and indeed he is great in all his offices of Prophet, Priest, and King: and so is the blessed Spirit, who is equal to the Father and Son, and greater than he that is in the world. Now all this the psalmist could say from his own knowledge; he knew the Lord was great, from the consideration and meditation of his wondrous works; he knew the greatness of Christ, from the revelation made to him of his person, offices, and grace; he knew the greatness of the divine Spirit, from the inward experience of his upon his heart, as well as from his being divinely inspired by him; and because of this greatness of the Lord, as well as his goodness, he is to be praised; it is mentioned as a reason of it;
and that our Lord is above all gods; the Lord our righteousness; Immanuel, God with us: our Lord, not only by right of creation, but of redemption; he is above all that the Heathens called gods, even the greatest of them; not the idols their hands made only, but the heavens and all the host of them, the sun, moon, and stars; his glory is above them, being the Maker of them, as God; and he is made higher than they, as man and Mediator: he is above civil magistrates, princes, and kings of the earth, called gods, Psalm 82:5; he is King of kings, and Lord of lords, he is higher than they; by him they reign, and to him they are accountable; and he is above the angels, sometimes called "Elohim", or gods, Psalm 8:5; he has a more excellent name and nature than they; he is the Creator of them, the object of their worship, to whom they minister, whose servants they are; and he is now exalted above them in the human nature, at the right hand of God; see Hebrews 1:4.

God is, and will be always, the same to his church, a gracious, faithful, wonder-working God. And his church is, and will be, the same to him, a thankful, praising people: thus his name endures for ever. He will return in ways of mercy to them, and will delight to do them good.

The praise itself now begins. כּי in Psalm 135:4 set forth the ground of the pleasant duty, and the כי that begins this strophe confirms that which warrants the summons out of the riches of the material existing for such a hymn of praise. Worthy is He to be praised, for Israel knows full well that He who hath chosen it is the God of gods. The beginning is taken from Psalm 115:3, and Psalm 135:7 from Jeremiah 10:13 (Psalm 51:16). Heaven, earth, and water are the three kingdoms of created things, as in Exodus 20:4. נשׂיא signifies that which is lifted up, ascended; here, as in Jeremiah, a cloud. The meaning of בּרקים למּטר עשׂה is not: He makes lightnings into rain, i.e., resolves them as it were into rain, which is unnatural; but either according to Zac 10:1 : He produces lightnings in behalf of rain, in order that the rain may pour down in consequence of the thunder and lightning, or poetically: He makes lightnings for the rain, so that the rain is announced (Apollinaris) and accompanied by them. Instead of מוצא (cf. Psalm 78:16; Psalm 105:43), which does not admit of the retreating of the tone, the expression is מוצא, the ground-form of the part. Hiph. for plurals like מחצרים, מחלמים, מעזרים, perhaps not without being influenced by the ויּוצא in Jeremiah, for it is not מוצא from מצא that signifies "producing," but מוציא = מפיק. The metaphor of the treasuries is like Job 38:22. What is intended is the fulness of divine power, in which lie the grounds of the origin and the impulses of all things in nature.