Albert Barnes Commentary Psalms 44:2

"Thou didst drive out the nations with thy hand; But them thou didst plant: Thou didst afflict the peoples; But them thou didst spread abroad." — Psalms 44:2 (ASV)

How thou didst drive out the heathen with thy hand - The word rendered “heathen” means simply nations, without necessarily conveying the idea of paganism as that word is now understood. It means the nations, namely, of the land of Canaan, or the Canaanites. Since these nations were in fact idolaters, or strangers to the true religion, the word came in time to have that idea attached to it. It is in that sense that we use the term now, though the word “nations” would accurately express the meaning of the original.

The word rendered “drive out” - ירשׁ yârash - properly means to take, seize, or take possession of. Then, in the form used here (Hiphil), it means to cause to possess, to give possession of, and then, to take possession of, to drive out of a possession, to dispossess, or to disinherit. The meaning here is, he dispossessed them of their country; he disinherited them. This, the psalmist says, God had done by his hand; that is, it was by his own power.

And plantedst them - That is, he planted his people—the children of Israel. He put them in the place of those whom he had disinherited or dispossessed. The word is properly applicable to a tree but is also used with reference to a nation, meaning that he assigned them a fixed and permanent residence. Thus we say in English, “to plant a colony.” Compare Amos 9:15; Jeremiah 24:6; Jeremiah 32:41; Psalms 80:8; 2 Samuel 7:10.

How thou didst afflict the people - That is, the people of the land of Canaan; the nations that dwelt there. The word means to bring evil or calamity upon anyone.

And cast them out - The word used here can be understood in the sense of sending out or expelling (1 Kings 9:7). In that case, it would apply to the Canaanites, meaning that God had expelled or driven them out, as our translators understand it. Alternatively, the word may be used to denote the sending out of shoots or branches by a tree or vine (Jeremiah 17:8; Ezekiel 17:6–7). If so, it would refer here to the Israelites, meaning that God caused them to increase, multiplied them, and spread them over the land as a vine spreads (Psalms 80:8–11). The parallelism here clearly demands the latter interpretation. So it is understood by Luther, DeWette, Tholuck, and Prof. Alexander.