(6.) He engages to prepare them for these temporal mercies which he designed for them by bestowing spiritual mercies upon them, v.7. It is this that will make their captivity be for their good; this shall be both the improvement of their affliction and their qualification for deliverance. When our troubles are sanctified to us, then we may be sure that they will end well. Now that which is promised is, [1.] That they should be better acquainted with God; they should learn more of God by his providences in Babylon than they had learned by all his oracles and ordinances in Jerusalem, thanks to divine grace, for, if that had not wrought mightily upon them in Babylon, they would for ever have forgotten God. It is here promised, I will give them, not so much a head to know me, but a heart to know me, for the right knowledge of God consists not in notion and speculation, but in the convictions of the practical judgment directing and governing the will and affections. A good understanding have all those that do his commandments, Ps. cxi. 10. Where God gives a sincere desire and inclination to know him he will give that knowledge. It is God himself that gives a heart to know him, else we should perish for ever in our ignorance. [2.] That they should be entirely converted to God, to his will as their rule, his service as their business, and his glory as their end: They shall return to me with their whole heart. God himself undertakes for them that they shall; and, if he turn us, we shall be turned. This follows upon the former; for those that have a heart to know God aright will not only turn to him, but turn with their whole heart; for those that are either obstinate in their rebellion, or hypocritical in their religion, may truly be said to be ignorant of God. [3.] That thus they should be again taken into covenant with God, as much to their comfort as ever: They shall be my people, and I will be their God. God will own them, as formerly, for his people, in the discoveries of himself to them, in his acceptance of their services, and in his gracious appearances on their behalf; and they shall have liberty to own him for their God in their prayers to him and their expectations from him. Note, Those that have backslidden from God, if they do in sincerity return to him, are admitted as freely as any to all the privileges and comforts of the everlasting covenant, which is herein well-ordered, that every transgression in the covenant does not throw us out of covenant, and that afflictions are not only consistent with, but flowing from, covenant-love.