Luther here argues that Christians ought to be assured of their salvation, and that to say otherwise is a wicked lie of the devil meant to rob you of this blessed right as a Christian. Most importantly, he argues that the sufficient evidence that we are possessors of the Holy Spirit is our faith in the word of God, our embracing of and desire for the truth of the Gospel, and our confession of Jesus Christ, the testimony of our lips. This is a most astute and Biblical observation that is generally missed by many. While Luther does give some assent to the idea that Christians will do good works, it is clear in this passage that he didn't put much weight upon that, and even objected to it by saying that "there is no great difference betwixt a Christian and a civil honest man." If that is the case, our good works cannot therefore be sufficient evidence of our salvation, even if they do provide some confirmation of it. Assurance of salvation ultimately derives from our faith, our new understanding of divine things, our embrace of the truth, and the fruit of our lips. This is precisely what the Bible teaches.
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"The Holy Ghost is sent by the Word into the hearts of the believers, as here it is said, ‘God sent the spirit of his Son,’ etc. This sending is without any visible appearance; to wit, when by the hearing of the spoken Word, we receive an inward fervency and light, whereby we are changed and become new creatures; whereby also we receive a new judgment, new feelings and motions. This change and this new judgment is no work of reason, or of the power of man, but is the gift and the operation of the Holy Ghost, which cometh with the Word preached, which purifieth our hearts by faith, and bringeth forth in us spiritual motions. Therefore there is a great difference betwixt us and those which with force and subtlety persecute the doctrine of the Gospel. For we by the grace of God can certainly judge by the Word, of the will of God towards us; also of all laws and doctrines, of our own life and of the life of others. Contrariwise, the Papists and Sectaries cannot certainly judge of anything. For they corrupt, they persecute and blaspheme the Word. Now without the Word a man can give no certain judgment of anything.
And although it appear not before the world, that we be renewed in mind and have the Holy Ghost, yet notwithstanding our judgment, our speech, and our confession do declare sufficiently, that the Holy Ghost with his gifts is in us. For before we could judge rightly of nothing. We spake not as now we do. We confessed not that all our works were sin and damnable; that Christ was our only merit both before grace and after, as now we do in the true knowledge and light of the Gospel. Wherefore let this trouble us nothing at all, that the world (whose works we testify to be evil) judgeth us to be most pernicious heretics and seditious persons, destroyers of religion, and troublers of the common peace, possessed of the devil speaking in us and governing all our actions. Against this perverse [and wicked] judgment of the world, let this testimony of our conscience be sufficient, whereby we assuredly know, that it is the gift of God, that we do not only believe in Jesus Christ, but that we also preach and confess him openly before the world. As we believe with our heart, so do we speak with our mouth, according to that saying of the Psalmist: ‘I believed, and therefore I have spoken etc.’ (Psalm 115:10).
Moreover we exercise ourselves unto godliness and avoid sin as much as we may. If we sin, we sin not of purpose, but of ignorance, and we are sorry for it. We may slip, for the devil lieth in wait for us both day and night. Also the remnants of sin cleave yet fast in our flesh: therefore as touching the flesh we are sinners, yea, after that we have received the Holy Ghost. And there is no great difference betwixt a Christian and a civil honest man. For the works of a Christian in outward shew are but base and simple. He doth his duty according to his vocation, he governeth the commonwealth, he guideth his family, he tilleth the ground, he giveth counsel, he aideth and succoureth his neighbour. These works the carnal man doth not much esteem, but thinketh them to be common and nothing worth, being such as the laity, yea the heathen also do. For the world understandeth not the things which are of the Spirit of God, and therefore it judgeth perversely of the works of the godly. But the monstrous superstition of hypocrites and their will-works they have in great admiration. They count them holy works, and spare no charges in maintaining the same. Contrariwise, the works of the faithful (which although in outward appearance they seem to be but vile and nothing worth, yet are they good works indeed, and accepted of God, because they are done in faith, with a cheerful heart, and with obedience and thankfulness towards God), these works, I say, they do not only not acknowledge to be good works, but also they despise and condemn them as most ungodly and unrighteous. The world therefore believeth nothing less than that we have the Holy Ghost. Notwithstanding in the time of tribulation or of the cross, and of the confession of our faith (which is the proper and principal work of those that believe), when we must either forsake wife, children, goods and life, or else deny Christ, then it appeareth that we make confession of our faith, that we confess Christ and his Word, by the power of the Holy Ghost.
We ought not therefore to doubt whether the Holy Ghost dwelleth in us or not; but to be assuredly persuaded that we ‘are the temple of the Holy Ghost,’ as Paul saith (1 Corinthians 6:19). For if any man feel in himself a love towards the Word of God, and willingly heareth, talketh, writeth, and thinketh of Christ, let that man know that it is not the work of man’s will or reason, but the gift of the Holy Ghost; for it is impossible that these things should be done without the Holy Ghost. Contrariwise, where hatred and contempt of the Word is, there the devil, the god of this world, reigneth, blinding men’s hearts and holding them captive, that the light of the glorious Gospel of Christ should not shine upon them (2 Corinthians 4:4). Which thing we see at this day in the most part of the common people, which have no love to the Word, but condemn it as though it pertained nothing at all unto them. But whosoever do feel any love or desire to the Word, let them acknowledge with thankfulness, that this affection is poured into them by the Holy Ghost. For we bring not this affection and desire with us; neither can we be taught by any laws how we may obtain it: but this change is plainly and simply the work of the right hand of the Most High. Therefore, when we willingly and gladly hear the Word preached concerning Christ the Son of God, who for us was made man and became subject to the law, that he might redeem us: then God, by and with this preaching, assuredly sendeth the Holy Ghost into our hearts. Wherefore it is very expedient for the godly to know, that they, have the Holy Ghost.
This I say, to confute that pernicious doctrine of the sophisters and monks, which taught that no man can certainly know (although his life be never so upright and blameless) whether he be in the favor of God or no. And this sentence, commonly received, was a special principle and article of faith in the whole Papacy, whereby they utterly defaced the doctrine of faith, tormented men’s consciences, banished Christ out of the Church, darkened and denied all the benefits and gifts of the Holy Ghost, abolished the true worship of God, set up idolatry, contempt of God, and blasphemy against God in men’s hearts. For he that doubteth of the will of God towards him, and hath no assurance that he is in grace, cannot believe that he hath remission of sins, that God careth for him, and that he can be saved.
Augustine saith very well and godly, that every man seeth most certainly his own faith, if he have faith. This do they deny. God forbid (say they) that I should assure myself that I am under grace, that I am holy, and that I have the Holy Ghost, yea, although I live godly, and do all works. Ye which are young, and are not infected with this pernicious opinion (whereupon the whole kingdom of the Pope is grounded), take heed and fly from it, as from a most horrible plague. We that are old men have been trained up in this error even from our youth, and have been so nusled therein, that it hath taken deep root in our hearts. Therefore it is to us no less labor to unlearn and forget the same, than to learn and lay hold upon true faith. But we must be assured and out of doubt that we are under grace, that we please God for Christ’s sake, and that we have the Holy Ghost. ‘For if any man have not the spirit of Christ, the same is none of his’ (Romans 8:9).
Moreover, whatsoever a man doubting thinketh, speaketh, or doeth, it is sin; for whatsoever proceedeth not of faith, is sin. Wherefore, whether thou be a minister of God’s Word, or a magistrate in the commonwealth, thou must assuredly think that thy office pleaseth God: but this thou canst never do, unless thou have the Holy Ghost. But thou wilt say: I doubt not but that my office pleaseth God, because it is God’s ordinance; but I doubt of mine own person whether it please God or no. Here thou must resort to the Word of God, which especially seeketh to assure us, that not only the office of the person, but also the person itself pleaseth God. For the person is baptized, believeth in Christ, is purged in his blood from all sins, liveth in the communion and fellowship of his Church. Moreover, he doth not only love the pure doctrine of the Word, but also is glad and greatly rejoiceth when he seeth it advanced, and the number of the faithful increased. Contrariwise, he detesteth the Pope and all Sectaries with their wicked doctrine, according to that saying of the Psalm: ‘I hate them that imagine evil things, but thy law do I love’ (Psalm 119:113).
We ought therefore to be surely persuaded, that not only our office, but our person pleaseth God: yea, whatsoever it saith, doth, or thinketh particularly, the same pleaseth God, not for our own sakes, but for Christ’s sake, whom we believe to have been made under the law for us. Now we are sure that Christ pleaseth God, that he is holy, etc. Forasmuch then as Christ pleaseth God and we are in him, we also please God and are holy. And although sin do still remain in our flesh, and we do also daily fall and offend, yet grace is more abundant and stronger than sin. The mercy and truth of the Lord reigneth over us forever. Wherefore sin cannot terrify us and make us doubtful of the grace of God [which is] in us. For Christ, that most mighty giant, hath quite abolished the law, condemned
sin, vanquished death, and all evils. So long as he is at the right hand of God, making intercession for us, we cannot doubt of the grace [and favor] of God towards us.
Moreover, God hath also sent the Spirit of his Son into our hearts, as Paul here saith. But Christ is most certain in his spirit that he pleaseth God, etc.; therefore we also, having the same spirit of Christ, must be assured that we are under grace for his sake, who is most assured. This I have said concerning the inward testimony, whereby a [Christian man’s] heart ought to be fully persuaded that he is under grace and hath the Holy Ghost. Now, the outward signs (as before I have said) are, gladly to hear of Christ, to preach and teach Christ, to render thanks unto him, to praise him, to confess him, yea, with the loss of goods and life: moreover, to do our duty according to our vocation as we are able, in faith, joy, etc.; not to delight in sins, nor to thrust ourselves into another man’s vocation, but to attend upon our own, to help our needy brother, to comfort the heavy hearted, etc. By these signs as by certain effects and consequents we are fully assured and confirmed, that we are in God’s favor. The wicked also imagine that they have the same signs, but they have nothing less. Hereby we may plainly perceive that the Pope with his doctrine doth nothing else, but trouble and torment men’s consciences, and at length drive them into desperation. For he not only teacheth, but also commandeth men to doubt. Therefore as the Psalm saith: ‘There is no [truth or] certainty in his mouth’ (Psalm 5:9). And in another place: ‘Under his tongue is iniquity and mischief’ (Psalm 10:7).
Here we may see what great infirmity is yet in the faith of the godly. For if we could be fully persuaded that we are under grace, that our sins are forgiven, that we have the spirit of Christ, that we are the children of God; then doubtless we should be joyful and thankful to God for this inestimable gift. But because we feel contrary motions, that is to say, fear, doubtfulness, anguish and heaviness of heart, and such-like, therefore we cannot assure ourselves hereof; yea our conscience judgeth it a great presumption and pride to challenge this glory. Wherefore, if we will understand this thing rightly and as we should do, we must put it in practice; for without experience and practice it can never be learned.
Wherefore let every man so practice with himself, that his conscience may be fully assured that he is under grace, and that his person and his works do please God. And if he feel in himself any wavering or doubting, let him exercise his faith and wrestle against this doubting, and let him labor to attain more strength and assurance of faith, so that he may be able to say: I know that I am accepted, and that I have the Holy Ghost; not for mine own worthiness, my work, my merit, but for Christ’s sake, who for our sakes made himself thrall and subject to the law, and took away the sins of the world. In him do I believe. If I be a sinner and err, he is righteous and cannot err. Moreover, I gladly hear, read, sing and write of him, and I desire nothing more than that his Gospel may be known to the whole world, and that many may be converted unto him.
These things do plainly witness that the Holy Ghost is present [with us and in us]. For such things are not wrought in the heart by man’s strength, nor gotten by man’s industry or travail, but are obtained by Christ alone, who first maketh us righteous by the knowledge of himself, and afterwards he createth a clean heart in us, bringeth forth new motions, and giveth unto us that assurance whereby we are persuaded that we please the Father for his sake. Also he giveth us a true judgment whereby we prove and try those things which before we knew not, or else altogether despised. It behoveth us therefore to wrestle against this doubting, that we may daily overcome more and more, and attain to a full persuasion and certainty of God’s favor towards us, rooting out of our hearts this cursed opinion (that a man ought to doubt of the grace and favor of God), which hath infected the whole world. For if we be not sure that we are in grace, and that we please God for Christ’s sake, then we deny that Christ hath redeemed us, we utterly deny all his benefits. Ye that are young, can easily lay hold on the doctrine of the Gospel and shun that pestilent opinion, wherewith ye have not yet been infected."
-- Martin Luther