I will bring them again to place them - Zechariah seems to have condensed into one word two of Jeremiah, “I will bring them again” unto this place, and “I will cause them to dwell” safely Jeremiah 32:37. Kimchi. It is not a confusion of forms, but the blending of two words into one. So also Ibn Ezra): “The two ideas are here both implied, he will cause them to return to their land, and will cause them to dwell there in peace and security.”
For I will have mercy upon them - Dionysius: “For the goodness and lovingkindness of God, not any merits of our‘s, is the first and principal cause of our whole salvation and grace. Therefore the Psalmist says, ‹neither did their own arm save them; but Thy right hand and Thine arm, and the light of Thy countenance, because Thou hadst a favor unto them‘ Psalm 44:3.”
And they shall be, as though I had not cast them off - (Etymologically, “loathed,” “cast off as a thing abhorrent”.) God is ever “the God of the present.” He does not half-forgive. “Their sins and their iniquities I will remember no more” Hebrews 8:12. God casts off the sinner, as being what he is, a thing abhorrent, as penitence confesses of itself that it is “a dead dog, a loathsome worm, a putrid corpse.” God will not clothe with a righteousness, which He does not impart. He restores to the penitent all his lost graces, as though he had never forfeited them, and cumulates them with the fresh grace whereby He converts him (see vol. i. on Joel 2:25, pp. 192,193). It is an entire re-creation. “They shall be, as though I had not cast them off.” “I will settle you as in your old estates, and will do good, more than at your beginnings, and ye shall know that I am the Lord” Ezekiel 36:11.
For I am the Lord their God, and will hear them - As He says by Malchi, “I am the Lord; I change not” Malachi 3:6. His unchangeableness belongs to His Being; “I Am; therefore ye sons of Jacob are not consumed;” and by Hosea, “The Lord of hosts, The Lord is His memorial, therefore turn thou to thy God” (Hosea 12:5-6, (6,7 Heb.) See vol. i. pp. 119,120). Because God was “their God,” and as surely as He was “their God,” He would hear them. His Being was the pledge of His hearing. “I, the Lord, will hear them; I, the God of Israel, will not forsake them” Isaiah 41:17.