Adiaphora are not to deny Christian freedom, replace true worship, or interfere with the preservation of the pure doctrine...

The article about Christian freedom is at stake here. The Holy Spirit, through the holy apostle’s mouth, sincerely told His Church to preserve this article, as we have just heard. As soon as Christian freedom is weakened and human traditions are forced on the Church with coercion, as though it were wrong and a sin to omit them, the way is already prepared for idolatry. In this way, human traditions are multiplied and regarded as a divine worship, not only equal to God’s ordinances, but even placed above them.

Furthermore, idolaters are confirmed in their idolatry by such yielding and conforming in outward things, where there has not previously been Christian unity in doctrine. On the other hand, true believers are grieved, offended, and weakened in their faith. Every Christian, for the sake of his soul’s welfare and salvation, is bound to avoid both of these, as it is written:

Woe to the world for temptations to sin! (Matthew 18:7)

But whoever causes one of these little ones who believe in Me to sin, it would be better for him to have a great millstone fastened around his neck and to be drowned in the depth of the sea. (Matthew 18:6)

But what Christ says is to be especially remembered:

So everyone who acknowledges Me before men, I also will acknowledge before My Father who is in heaven. (Matthew 10:32)

However, this has always and everywhere been the faith and confession about such matters, by the chief teachers of the Augsburg Confession. We are following in their footsteps and we intend to persevere in their confession by God’s grace.

~BOC, FSD, X, 15-18

Christ as our sole Mediator, Atoning Sacrifice, High Priest, and Intercessor...

Our churches teach that the history of saints may be set before us so that we may follow the example for their faith and good words, according to our calling.  For example, the emperor may follow the example of David in making war to drive away the Turk from his country.  For both are kings.  But the Scriptures do not teach that we are to call on the saints to to ask the saints for help.  Scripture sets before us the one Christ as the Mediator, Atoning Sacrifice, High Priest, and Intercessor.  He is to be prayed to. He has promised that He will hear our prayer.  This is the worship that He approves above all other worship, that He be called upon in all afflictions.  "If anyone does sin, we have an advocate with the Father" (I John 2:1).
~BOC, AC, XXI, 1-4

We will not overlook error or be silent, will not speak or write anything contrary to this Confession...

Our opponents have shameless mouths that have shouted allegations throughout the whole world against our churches and teachers.  They claimed that you cannot find two preachers who agree about each and every article of the Augsburg Confession, but that they are torn apart and separated from one another to such an extent that they themselves no longer know what the Augsburg Confession is and what its proper meaning is.  Therefore, we did not present this common Confession briefly or merely by signing our names, but we wanted to make a pure, clear, distinct declaration about all the disputed articles that have been discussed and argued among the theologians of the Augsburg Confession.  We did this so that everyone may see we do not want to hide or cover up all this in a cunning way or come to agreement only in appearance.  We want to remedy the matter thoroughly, and wanted to set forth our opinion on these matters in such a way that even our adversaries themselves must confess that in all this we abide by the true, simple, natural, and proper sense of the Augsburg Confession.  We desire, by God's grace, to persevere constantly in this confession until our end.  And as long as it depends on our ministry, we will not overlook error or be silent, lest anything contrary to the genuine sense of the Augsburg Confession is introduced into our churches and schools, in which the almighty God and Father of our Lord Jesus Christ has appointed us teachers [Latin: doctors] and pastors.

...

In the sight of God and of all Christendom, we want to testify to those now living and those who will come after us.  This declaration presented here about on the controverted articles mentioned and explained above--and no other--is our faith, doctrine, and confession.  By God's grace, with intrepid hearts, we are willing to appear before the judgment seat of Christ with this Confession and give an account to it.  We will not speak or write anything contrary to this Confession, either publicly or privately.  By the strength of God's grace we intend to abide by it.  Therefore, after mature deliberation, we have, in the fear of God and by calling on His name, attached our signatures with our own hands.
~BOC, FSD, XII, 3-6, 40

The cause of our sin is our own will...

Our churches teach that although God creates and preserves nature, the cause of sin is located in the will of the wicked, that is, the devil and ungodly people.  Without God's help, this will turns itself away from God, as Christ says, "When he lies, he speaks out of his own character" (John 8:44).
~BOC, AC, XIX

Christian righteousness is the faith that believes that sins are freely forgiven for Christ's sake...

Not only the people, but also those teaching in the churches, have generally been persuaded to believe in making distinctions between meats, and similar human traditions.  They believe these are useful works for meriting grace and are able to make satisfaction for sins.  From this there developed that new ceremonies, new orders, new holy days, and new fastings were instituted daily.  Teachers in the Church required these works as a necessary service to merit grace.  They greatly terrified people's consciences when they left any of these things out.  Because of this viewpoint, the Church has suffered great damage.

First, the chief part of the Gospel--the doctrine of grace and of the righteousness of faith--has been obscured by this view.  The Gospel should stand out as the most prominent teaching in the Church, in order that Christ's merit may be well known and faith, which believes that sins are forgiven for Christ's sake, be exalted far above works.  Therefore, Paul also lays the greatest stress on this article, putting aside the Law and human traditions, in order to show that Christian righteousness is something other than such works.  Christian righteousness is the faith that believes that sins are freely forgiven for Christ's sake.  But this doctrine of Paul has been almost completely smothered by traditions, which have produced the opinion that we must merit grace and righteousness by making distinctions in meats and similar services.  When repentance was taught, there was no mention made of faith.  Only works of satisfaction were set forth.  And so repentance seemed to stand entirely on these works.
~BOC, AC, XXVI, 1-7

It is the passion of Christ, not the act of a Mass, that forgives, justifies...

An opinion was added that infinitely increased private Masses.  It states that Christ, by His passion, made satisfaction for original sin and instituted the Mass as an offering for daily sins, both venial and mortal.  From this opinion has arisen the common belief that the Mass takes away the sins of the living and the dead simply by performing the outward act.  Then they began to argue about whether one Mass said for many is worth as much as special Masses for individuals.  This resulted in an infinite number of Masses.  With this work, people wanted to obtain from God all that they needed, and in the meantime, trust in Christ and true worship were forgotten.

Our teachers have warned that these opinions depart from the Holy Scripture and diminish the glory of the passion of Christ.  For Christ's passion was an offering and satisfaction, not only for original guilt, but also for other sins, as it is written, "We have been sanctified through the offering of the body of Jesus Christ once for all, (Hebrews 10:10).  Also, "By a single offering He has perfected for all time those who are being sanctified" (Hebrews 10:14).  (It is an unheard-of innovation in the Church to teach that by His death Christ has made satisfaction only for original sin and not for all other sin.  So it is hoped that everybody will understand that this error has been rebuked for good reason),

Scripture teaches that we are justified before God, through faith in Christ, when we believe that our sins are forgiven for Christ sake. Now if the Mass takes away the sins of the living and the dead simply by performing it, justification comes by doing Masses, and not of faith.  Scripture does not allow this.
~BOC, AC, XXIV, 21-29

Without faith we can do no good for nothing in man is harmless...

Therefore, it is easy to see that this doctrine is not to be accused of banning good works.  Instead, it is to be commended all the more because it shows how we are enabled to do good works.  For without faith, human nature cannot, in any way, do the works of the First or Second Commandment.  Without faith, human nature cannot call upon God, nor expect anything from Him, nor bear the cross.  Instead human nature seeks and trusts in human help.  So when there is no faith and trust in God, all kinds of lusts and human intentions rule in the heart.  This is why Christ says, "Apart from me you can do nothing" (John 15:5). That is why the Church sings: "Lacking Your divine favor, there is nothing in man.  Nothing in him is harmless."
~BOC, AC, XX, 35-40

Without faith one cannot believe in the forgiveness of sins...

The person who knows that he has a Father who is gracious to him through Christ truly knows God.  He also knows that God cares for him.  In a word, he is not without God, as are the heathen.  For devils and the ungodly are not able to believe this article: the forgiveness of sins. Hence, they hate God as an enemy and do not call Him and expect no good from Him.  Augustine also warns his readers about the word faith and teaches that the term is used in Scriptures, not for the knowledge that is in the ungodly, but for the confidence that consoles and encourages the terrified mind.
~BOC, AC, XX, 24-26

Consolation for the conscience plagued by works...

Until now, consciences were plagued with the doctrine of works.  They did not hear consolation from the Gospel.  Some people were driven by conscience into the desert and into monasteries, hoping to merit grace by a monastic life.  Some people came up with other works to merit grace and make satisfaction for sin.  That is why the need was so great for teaching and renewing the doctrine of faith in Christ, so that anxious consciences would not be without consolation but would know that grace, forgiveness of sins, and justification are received by faith in Christ.
~BOC, AC, XX, 19-22

The Sacraments and Word are effective because of Christ's institution and command...

Strictly speaking, the Church is the congregation of saints and true believers.  However, because many hypocrites and evil persons are mingled within them in this life, it is lawful to use the Sacraments administered by evil men, according to the saying of Christ, "The scribes and the Pharisees sit on Moses' seat" (Matthew 23:2). Both the Sacraments and Word are effective because of Christ's institution and command, even if they are administered by evil men.
~BOC, AC, VIII, 1-2

Do not bondage people to the Law with man-made traditions...

Those who establish such traditions* are acting contrary to God's command when they locate sin in foods, days, and similar things.  They burden the Church with bondage to the law, as if there needs to be something similar to the services commanded in Leviticus [chapters 1-7] in order to merit justification....It is necessary for the chief article of the Gospel be preserved, namely that we obtain grace freely by faith in Christ, and not by certain observances or acts of worship devised by people.
~BOC, AC, XXVIII, 39, 52

*ones for the purpose of making satisfaction of sins or to merit grace or righteousness (see 35)

The use and benefit of the Lord's Supper is why it was offered every holy day and when anyone desired it...

The people are also advised about the dignity and use of the Sacrament [The Lord's Supper], about how it brings great consolation to anxious consciences, so that they, too, may learn to believe God and to expect and ask from Him all that is good. This worship pleases God. ...Because the Mass is for the purpose of giving the Sacrament, we have Communion every holy day, and if anyone desires the Sacrament, we also offer it on other days, when it is given to all who ask for it.
~BOC, AC, XXIV, 7-8, 34

The natural person does not accept the things of God...

It [human will] has no power, without the Holy Spirit, to work the righteousness of God, that is, spiritual righteousness. For the "natural person does not accept the things of the Spirit of God" (I Cor. 2:14). This righteousness is worked in the heart when the Holy Spirit is received through the Word.
~BOC, AC, XVIII, 1-3

Righteousness not found in self-chosen practices and acts of worship...

Paul teaches everywhere that righteousness is not to be sought in self-chosen practices and acts of worship, devised by people. Righteousness comes by faith to those who believe that they are received by God into grace for Christ's sake.
~BOC, AC, XXVII, 37

The Sacraments awaken and confirm faith...

They [the Sacraments] were instituted to awaken and confirm faith in those who use them.  Therefore, we must use the Sacraments in such a way that faith, which believes the promises offered and set forth through the Sacraments, is increased.
~BOC, AC, XIII, 2

What we receive through faith...

The forgiveness of sins and justification is received through faith. The voice of Christ testifies, "So you also, when you have done all that you were commanded, say, 'We are unworthy servants; we have only done what was our duty'" (Luke 17:10). The Fathers teach the same thing. Ambrose says, "It is ordained of God that he who believes in Christ is saved, freely receiving forgiveness of sins, without works, through faith alone.
~BOC, AC, VI, 2-3

The Gospel is incompatible with the teaching of merited grace...

The Gospel compels us to insist on the doctrine of grace and the righteousness of faith in the churches.  This cannot be understood if people think that they merit grace by observances of their own choice.
~BOC, AC, XXVI, 20

Objective Grace brings the greatest consolation to anxious souls...

Spiritually inexperienced people despise this teaching [objective grace]. However, God-fearing and anxious consciences find by experience that it brings the greatest consolation. Consciences cannot be set at rest through any works, but only by faith, when they take the sure ground that for Christ's sake they have a gracious God.
~BOC, AC, XX, 15-16

God's voice sounding from heaven...

Our people are taught that they should highly prize the Absolution as being God's voice and pronounced by God's command. The Power of the Keys is set forth in its beauty. They are reminded what great consolation it brings to anxious consciences and that God requires faith to believe such Absolution as a voice sounding from heaven.
~BOC, AC, XXV, 3-4

The Sacraments are signs and testimonies of God's will toward us...

Our church teaches that the Sacraments were ordained, not only to be marks of profession among men, but even more, to be signs and testimonies of God's will toward us. They were instituted to awaken and confirm faith in those who use them. Therefore, we must use the Sacraments in such a way that faith, which believes the promises offered and set forth through the Sacraments is increased.
~BOC, AC, XIII, 1-2