Found over on Gottesdienst Online
Does God promise both temporal and eternal rewards to our good works?
What! Are you kidding? I mean, if you believed that, you’d be a Gospel denying Romanist or a Fundy TV evangelist, right? Law driven! Bad!
Or, then again, if you believed that maybe you’d be the greatest Lutheran theologian ever.
This teaching is set forth in our churches plainly and distinctly from the Word of God, namely, that the expiation of sins, or the propitiation for sins, must not be attributed to the merits of our works. For these things are part of the office which belongs to Christ the Mediator alone. Thus the remission of sins, reconciliation with God, adoption, salvation, and eternal life do not depend on our merits but are granted freely for the sake of the merit and obedience of the Son of God and are accepted by faith. Afterward, however, the good works in the reconciled, since they are acceptable through faith for the sake of the Mediator, have spiritual and bodily rewards in this life and after this life; they have these rewards through the gratuitous divine promise; not that God owes this because of the perfection and worthiness of our works, but because He, out of fatherly mercy and liberality, for the sake of Christ, has promised that He would honor with rewards the obedience of His children in this life, even though it is only begun and is weak, imperfect, and unclean. These promises should arouse in the regenerate a zeal for doing good works. For from this we understand how pleasing to the heavenly Father is that obedience of His children which they begin under the leading of the Holy Spirit in this life, while they are under this corruptible burden of the flesh, that He wants to adorn it out of grace and mercy for His Son’s sake with spiritual and temporal rewards which it does not merit by its own worthiness. And in this sense also our own people do not shrink back from the word “merit,” as it was used also by the fathers. For the rewards are promised by grace and mercy; nevertheless, they are not given to the idle or to those who do evil but to those who labor in the vineyard of the Lord.And so the word “merit” is used in the Apology of the Augsburg Confession, the Wuerttemberg Confession, and in other writings of our men. In this way and in this sense, we set forth the statements of Scripture in our churches about the rewards of good works. 1 Tim. 4:8: “Godliness is of value in every way, as it holds promise for the present life and also for the life to come.” Luke 14:14: “You will be repaid at the resurrection of the just.” Matt. 5:12: “Your reward is great in heaven.” Matt. 10:42: “He shall not lose his reward.” Gal. 6:9: “Let us not grow weary in well-doing, for in due season we shall reap, if we do not lose heart.” Eph. 6:8: “Knowing that whatever good any one does, he will receive the same again from the Lord.” Heb. 6:10: “God is not so unjust as to overlook your work and the love which you showed for His sake in serving the saints.” 2 Thess. 1:6–7: “Since indeed God deems it just to repay with affliction those who afflict you and to grant rest with us to you who are afflicted, etc.” Scripture is full of such promises of spiritual and bodily rewards.
That’s Chemnitz, the Examen, vol 1, page 653ff.
That’s what Lutherans believe. If you don’t, you are an Antinomian.