The humble will increase their joy in the LORD, and the poor among men will rejoice in the Holy One of Israel.
19. Then shall the humble again take joy in Jehovah. Such is my translation of this passage, while others render it, “They shall add,” or “continue to rejoice;” for the Prophet describes not a “joy” which is continued but rather a “joy” which is new.
Those that thought to hide their counsels from the Lord were said to turn things upside down (Isa 29:16), and they intended to do it unknown to God; but God here tells them that he will turn things upside down his way; and let us see whose word shall stand, his or theirs.
Commenting on Isaiah 29:17-24
The meek also shall increase their joy in the Lord,.... The "meek", lowly, and humble, are such who are made sensible of sin, and become humble under a sense of it; who see the insufficiency of their own righteousness, and submit to the righteousness of Christ; who attribute all they have, and are, to the free grace of God, and quietly submit to every dispensation...