John Gill's Exposition of the Whole Bible
Jeremiah 22:4
For if ye do this thing indeed,.... Or, "in doing do this word" y; diligently and carefully attend to this word of exhortation, and constantly perform the duties required:
then shall there enter in by the gates of this house kings sitting upon the throne of David; or, upon the throne for David: in his room and stead, as successors of his; or of his lineage and descent, as the Vulgate Latin version. The meaning is, that should the kings of Judah do the duty of their office, before pointed at, there should never be any want of successors of the seed of David; but there should be a race of kings descending from him, and sitting on his throne in all after ages, who should dwell in the royal palace, and go in and out at the gates of it; and they should also live in great pomp and splendour, in royal dignity, answerable to their characters:
riding in chariots, and on horses, he, and his servants, and his people; the king, his nobles, and other his attendants; some on one, and some on another, when they went out or came in; see Jeremiah 17:25.
y כי אם עשו תעשו את הדבר "si namque faciendo feceritis verbum hoc", Montanus, Schmidt.