Thou leddest thy people like a flock by the hand of Moses and Aaron - This satisfied and comforted the mind of the psalmist. God had never forsaken his people. He had shown himself faithful in his dealings with them. He had acted the part of a good shepherd. In all the dangers of their way; in their perilous journey through the wilderness; amidst foes, privations, and troubles - rocks, sands, storms, tempests - when surrounded by enemies, and when their camp was infested with poisonous serpents - God had shown himself able to protect his people, and had been faithful to all his promises and covenant-engagements. Looking back to this period of their history, the psalmist saw that there was abundant reason for confiding in God, and that the mind should repose on him calmly amid all that was dark and mysterious in his dealings. In view of the past, the mind ought to be calm; encouraged by the past, however incomprehensible may be God's doings, people may come to him, and entrust all their interests to him with the confident assurance that their salvation will be secure, and that all which seems dark and mysterious in the dealings of God will yet be made clear.

Thou leddest thy people like a flock - This may refer to the pillar of cloud and fire. It went before them, and they followed it. So, in the eastern countries, the shepherd does not drape, but leads, his flock. He goes before them to find them pasture, and they regularly follow him.
By the hand of Moses and Aaron - They were God's agents; and acted, in civil and sacred things, just as directed by the Most High.

Thou leddest thy people like a flock,.... Either through the Red sea, according to R. Moses Hacohen, as Aben Ezra observes; see Isaiah 63:11, or rather, as he and Kimchi, through the wilderness, after they were led through the sea; the people of Israel are compared to a flock of sheep; the Lord is represented as the Shepherd of them, who took care of them, protected and preserved them from their enemies:
by the hand of Moses and Aaron; the one was their civil and the other their ecclesiastical governor, and both under the Lord, and instruments of his, in guiding and conducting the people in all things needful for them. The Arabic version adds, "Allelujah"; from all this the psalmist concluded, though it is not mentioned, that as God had delivered his people of old out of their straits and difficulties, so he hoped and believed, that as he could, he would deliver him in his own time and way; and by this means his faith was relieved and strengthened.

If we have divided the strophes correctly, then this is the refrain-like close. Like a flock God led His people by Moses and Aaron (Numbers 33:1) to the promised goal. At this favourite figure, which is as it were the monogram of the Psalm of Asaph and of his school, the poet stops, losing himself in the old history of redemption, which affords him comfort in abundance, and is to him a prophecy of the future lying behind the afflictive years of the present.

Leddest - First through the sea, and afterwards through the wilderness, with singular care and tenderness, as a shepherd doth his sheep.