1)
Why does it mention raising the poor?
1.
Radak: Even though He is elevated, He descends to see the poor, and raises them.
2.
Malbim: This teaches how His Hashgachah descends to the lowest, and He raises them. The Mizmor refutes those who said that wealth, poverty, children and barrenness depend on Mazal and the Ma'arachah. Really, Hashgachah decides them. 'Hashem makes ladders; He makes this one poor and this one rich; He makes matches - 'Bas Ploni to Ploni' (Bamidbar Rabah 3:6). Even if the Ma'arachah mandated that Ploni be at the lowest level, and even an Evyon in the wasteheap, Hashem lifts him to the height of the world.
