The Mystical Union in the Lutheran Confessions

Afterward he [Christ] ascended into heaven to sit on the right hand of the Father, forever reign and have dominion over all creatures, and sanctify those who believe in him by sending the Holy Spirit into their hearts to rule, comfort, and quicken them and defend them against the devil and the power of sin. (Augsburg Confession III:4-5 [Latin], p. 30)

More than blind are those who do not believe that evil desires in the flesh are sins, about which Paul says (Gal. 5:17), “The desires of the flesh are against the Spirit, and the desires of the Spirit are against the flesh.” The flesh distrusts God and trusts in temporal things; in trouble it looks to men for help; it even defies God’s will and runs away from afflictions that it ought to bear because of God’s command; and it doubts God’s mercy. The Holy Spirit in our hearts battles against such feelings in order to suppress and destroy them and to give us new spiritual impulses. (Apology of the Augsburg Confession IV:169-70, p. 130)

The church is not merely an association of outward ties and rites like other civic governments, however, but it is mainly an association of faith and of the Holy Spirit in men’s hearts. To make it recognizable, this association has outward marks, the pure teaching of the Gospel and the administration of the sacraments in harmony with the Gospel of Christ. This church alone is called the body of Christ, which Christ renews, consecrates, and governs by his Spirit, as Paul testifies when he says (Eph.1:22,23), “And he has made him the head over all things for the church, which is his body, the fullness,” that is, the whole congregation “of him who fills all in all.” Thus those in whom Christ is not active are not members of Christ. (Apology VII/VIII:5, p. 169)

There is a long exposition of John 15 in Cyril which teaches that Christ is offered to us bodily in the Supper. He says: “We do not deny that we are joined to Christ spiritually by true faith and sincere love. But we do deny that we have no kind of connection with him according to the flesh, and we say that this would be completely foreign to the sacred Scriptures. Who has ever doubted that Christ is a vine in this way and that we are truly branches, deriving life from him for ourselves? Listen to Paul say, ‘We are all one body in Christ’ (Rom. 12:5); ‘We who are many are one body, for we all partake of the same loaf’ (1 Cor. 10:17). Does he think perhaps that we do not know the power of the mystical benediction? Since this is in us, does it not also cause Christ to dwell in us bodily through the communication of the flesh of Christ?” A little later he says, “Therefore we must consider that Christ is in us, not only according to the habit which we understand as love, but also by a natural participation,” etc. (Apology X:3, p. 179)

...works done according to the law are, and are called, works of the law as long as they are extorted from people only under the coercion of punishments and the threat of God’s wrath. Fruits of the Spirit, however, are those works which the Spirit of God, who dwells in the believers, works through the regenerated, and which the regenerated perform in so far as they are reborn and do them as spontaneously as if they knew of no command, threat, or reward. In this sense the children of God live in the law and walk according to the law of God. (Formula of Concord, Epitome VI:5-6, pp. 480-81)

We must also explain correctly the discussion concerning the indwelling of God’s essential righteousness in us. On the one hand, it is true indeed that God the Father, Son, and Holy Spirit, who is the eternal and essential righteousness, dwells by faith in the elect who have been justified through Christ and reconciled with God, since all Christians are temples of God the Father, Son, and Holy Spirit, who impels them to do rightly. But, on the other hand, this indwelling of God is not the righteousness of faith of which St. Paul speaks and which he calls the righteousness of God, on account of which we are declared just before God. This indwelling follows the preceding righteousness of faith, which is precisely the forgiveness of sins and the gracious acceptance of poor sinners on account of the obedience and merit of Christ. (Formula of Concord, Solid Declaration III:54, pp. 548-49)

...we unanimously reject and condemn...the following and all similar errors as contrary to the Word of God, the teaching of the prophets and apostles, and our Christian faith: ... That not God but only the gifts of God dwell in believers. (Solid Declaration III:59,65, p. 550)

...all who eat and drink the blessed bread and wine in the Lord’s Supper receive and partake of the true, essential body and blood of Christ orally. Believers receive it as a certain pledge and assurance that their sins are truly forgiven, that Christ dwells and is efficacious in them; unbelievers receive it orally, too, but to their judgment and damnation. (Solid Declaration VII:63, p. 581)

Next to the article of the holy Trinity, the greatest mystery in heaven and on earth is the personal union [of the two natures in Christ], as Paul says, “Great indeed is the mystery of our religion: God was manifested in the flesh” (I Tim. 3:16). Since St. Peter testifies with clear words that even we, in whom Christ dwells only by grace, have in Christ, because of this exalted mystery, “become partakers of the divine nature” (II Pet. 1:4), what kind of participation in the divine nature must that be of which the apostle says that “in Christ the whole fullness of deity dwells bodily” (Col. 2:9) in such a way that God and man are a single person! (Solid Declaration VIII:33-34, p. 597)

For while it is true that God, together with the whole fullness of deity which he always has with him, dwells in believers, he does not do so bodily nor is he personally united with them as is the case in Christ. (Solid Declaration VIII:70, p. 604)

We believe that...Christ can be and is present wherever he wills, and in particular that he is present with his church and community on earth as mediator, head, king, and high priest. Not part or only one-half of the person of Christ, but the entire person to which both natures, the divine and the human, belong is present. He is present not only according to his deity, but also according to and with his assumed human nature, according to which he is our brother and we flesh of his flesh and bone of his bone (Eph. 5:30). To make certainty and assurance doubly sure on this point, he instituted his Holy Supper that he might be present with us, dwell in us, work and be mighty in us according to that nature, too, according to which he has flesh and blood. (Solid Declaration VIII:78-79, pp. 606-07)

Hence we consider it a pernicious error to deprive Christ according to his humanity of this majesty [of the divine nature]. To do so robs Christians of their highest comfort, afforded them in the cited promises of the presence and indwelling of their head, king, and high priest, who has promised that not only his unveiled deity, which to us poor sinners is like a consuming fire on dry stubble, will be with them, but that he, the man who has spoken with them, who has tasted every tribulation in his assumed human nature, and who can therefore sympathize with us as with men and his brethren, he wills to be with us in all our troubles also according to that nature by which he is our brother and we are flesh of his flesh. (Solid Declaration VIII:87, p. 608)

...since the Holy Spirit dwells in the elect who have come to faith as he dwells in his temple, and is not idle in them but urges them to obey the commandments of God, believers likewise should not be idle, still less oppose the urgings of the Spirit of God, but should exercise themselves in all Christian virtues, in all godliness, modesty, temperance, patience, and brotherly love, and should diligently seek to “confirm their call and election” [II Pet. 2:10] so that the more they experience the power and might of the Spirit within themselves, the less they will doubt their election. For the Spirit testifies to the elect that they are “children of God” (Rom. 8:16). And if perchance they should fall into such grave temptation that they feel that they are no longer experiencing any power whatever of the indwelling Spirit of God and say with David, “I had said in my alarm, I am driven far from thy sight” (Ps. 31:22), then, regardless of what they experience within themselves, they should nevertheless join David in the next words, “But thou didst hear my supplications when I cried to thee for help” (Ps. 31:23). (Solid Declaration XI:73-74, p. 628)