In the fifth place, the Word of God is not rightly divided when sinners who have been struck down and terrified by the Law are directed, not to the Word and the Sacraments, but to their own prayers and wrestlings with God in order that they may win their way into a state of grace; in other words, when they are told to keep on praying and struggling until they feel that God has received them into grace.
The doctrine which is denounced in this thesis is common to all the Reformed and to the sects of Reformed origin, including the Baptists, the Methodists, the Evangelical Alliance, the Episcopalians, the Presbyterians. All these are only branches of the great tree of the Reformed Church. The pure evangelical doctrine of the way in which a poor, alarmed sinner arrives at the assurance that God is gracious to him is not heard among these people; this way is not shown by any of these sects.
Dr. Walther makes the point very well. When a sinner comes to understand that he’s a sinner in need of Christ’s salvation, what should be done? What did the apostles say such a sinner ought to do?
In order to obtain a divine assurance regarding the proper way of rightly dividing the Word, so as to meet the errors named in our thesis, let us examine a few pertinent examples recorded in Scripture. Let us observe the holy apostles, who were filled with the Holy Spirit and, being prompted by Him, no doubt divided the Word of God rightly and showed alarmed sinners the right way to rest and peace and assurance of their state of grace with God. […]
In Acts 2 we have a record of the way in which the Apostle Peter treated people who a few weeks previously had cried, “Crucify, crucify Him!” […] He showed them that the outpouring of the Holy Spirit was nothing but the fulfilment of Joel’s prophecy. He next rehearses the story of the suffering, death, resurrection, and final ascension of Jesus, concluding with these words: “Therefore let all the house of Israel know assuredly that God hath made that same Jesus whom ye have crucified both Lord and Christ.” […] “And they said to Peter and to the rest of the apostles, Men and brethren, what shall we do?” [..] How does the apostle act in this instance? Does he say: “You will have to make a personal effort to amend your conduct; you must come to a still more penitent knowledge of your sins; you must go down on your knees and cry for mercy; perhaps God will then help you and receive you into grace”? Nothing of the kind. He said to them: “Repent and be baptized, every one of you, in the name of Jesus Christ for the remission of sins.”
Should the sinner raise his hand or say a prayer to invite Jesus into his heart? Should the sinner dig deeply in his own perception of his soul, determining if he really has faith enough in the words spoken that he would be saved? Should the sinner perform all varieties of visible (and invisible) works that he may prove that he’s saved?
No. Concerning what looks an awful lot like modern “conversion methods”:
They give them a long list of efforts that they must make in order, if possible, to be received into grace: how long they must pray, how strenuously they must fight and wrestle and cry, until they can say that they feel they have received the Holy Ghost and divine grace and can rise from their knees shouting hallelujahs.
Concerning the biblical doctrine, instead:
Having this doctrine, what exceedingly happy and blessed people we Lutherans are! This teaching takes us to Christ by a straight route. It opens heaven to us when we feel hell in our hearts. It enables us to obtain grace at any moment without losing time by following a wrong way, striving for grace by our own effort, as we sometimes do with a good intention. We can approach Christ directly and say: “Lord Jesus, I am a poor sinner; I know it; that has been my experience in the past, and when I reflect what is going on in my heart now, I must say, that is still my experience. But Thou hast called me by Thy Gospel. I come to Thee just as I am; for I could come no other way.” That is the saving doctrine which the Evangelical Lutheran Church has learned from Christ and the apostles.
And here is the distinction between Lutherans and the modern FE churches, a different foundation of conversion that affects all of faith:
However, people imagine that, after Christ has done His share, man must still do his, and man is not reconciled to God until both efforts meet. The sects picture reconciliation as consisting in this, that the Savior made God willing to save men, provided men would be willing on their part to be reconciled. But that is the reverse of the Gospel. God is reconciled. Accordingly, the apostle Paul calls on us: “Be ye reconciled to God.” That means: Since God has been reconciled to you by Jesus Christ, grasp the hand which the Father in heaven holds out to you. Moreover, the apostle declares: “If one died for all, then were all dead.” 2 Cor. 5–14. That means: If Christ died for the sins of all men, that is tantamount to all men’s dying and making satisfaction for their sins. Therefore nothing at all is required on the part of man to reconcile God; He already is reconciled. Righteousness lies ready; it must not first be achieved by man. If man were to attempt to do so, that would be an awful crime, a battle against grace and against the reconciliation and perfect redemption accomplished by the Son of God.
In the second place, the sects teach false doctrine concerning the Gospel. They regard it as nothing else than an instruction for man, teaching him what he must do to secure the grace of God, while in reality the Gospel is God’s proclamation to men: “Ye are redeemed from your sins; ye are reconciled to God; your sins are forgiven.”
Check out more of Walther’s writing on this topic here.