.....by another person's actions, not his own.
Maybe, but that's not how I read it. He's saying that a person has not evidenced his justification if he hasn't forsaken everything for Christ.
Luke 14:25-35
25Now large crowds were going along with Him; and He turned and said to them, 26“If anyone comes to Me, and does not hate his own father and mother and wife and children and brothers and sisters, yes, and even his own life, he cannot be My disciple. 27“Whoever does not carry his own cross and come after Me cannot be My disciple. 28For which one of you, when he wants to build a tower, does not first sit down and calculate the cost to see if he has enough to complete it? 29Otherwise, when he has laid a foundation and is not able to finish, all who observe it begin to ridicule him, 30saying, ‘This man began to build and was not able to finish.’ 31“Or what king, when he sets out to meet another king in battle, will not first sit down and consider whether he is strong enough with ten thousand men to encounter the one coming against him with twenty thousand? 32“Or else, while the other is still far away, he sends a delegation and asks for terms of peace. 33So then, none of you can be My disciple who does not give up all his own possessions. 34Therefore, salt is good; but if even salt has become tasteless, with what will it be seasoned? 35It is useless either for the soil or for the manure pile; it is thrown out. He who has ears to hear, let him hear.”
Jesus said a person couldn't be his disciple. Bonhoeffer is using the concept of justification, but they're making the same point. Jesus has to be everything.
1 Corinthians 2:2
For I determined to know nothing among you except Jesus Christ, and Him crucified.
Was Peter a disciple? How about Paul? Did they literally leave all to follow Christ? Yes and no. They kept their clothes. Paul kept his entourage

. He kept his profession as a tentmaker. He kept his risk of self-exaltation (or the thorn in his side that kept him from manifesting it)

. James kept his seat on the council. We know Peter was married so, presumably he kept his wife in marriage even as he left to go establish congregations among the Jews in other locales. Bonhoeffer kept his writing, his family, his friends, his home. They were all eventually taken from him but there is a huge difference between leaving something and having that something taken from you. Was Bonhoeffer hypocritical while writing "
Cost of Discipleship"? No, I think not. What did I say at the beginning.
Depends on context.
Well, the words state what the words state and the words of the verse quoted state a man is justified by the work of another, NOT his own act(s). leaving everything would be an action of the already justified individual and I do not believe Bonhoeffer was suggesting a person could justify himself simply be leaving everything of his own behind to follow Christ.
Matthew 19:27
Then Peter responded and said to Him, “Behold, we have left everything and followed You; what then will there be for us?”
Was Peter
at that time justified before God? No! Temporally speaking, Calvary hadn't happened. No blood for Peter had yet been spent. God had claimed his life, but the payment had yet to be made. Leaving everything and following Jesus at
that point was nothing more than an earthly work of sinful flesh. It had no salvific merit whatsoever. By the time Jesus his last meal the crowd of disciples was large. By the time he stepped on Golgotha it had dwindled ad by the time he entered the grave everyone (with the possible exception of his mother and John) had abandoned him. Leaving everything to follow Jesus did not justify a single one of them. AFTER the price had been paid and the purchase was made those justified by the cross and the blood shed thereon would be expected to leave everything and thereby evidence their existing justification, the existence of their justification.
Jesus has to be everything. Gotta leave everything else to follow Jesus.
That is true..... except for that word "only." You know my view on this. It's called
onlyism; the practice of inserting the word "
only" into a verse where it does not exist. It's ironic in this case because we're discussing Bonhoeffer's statement on justification and folks have been divided, polarized, by siding with
only one side or another when the fact is all four causal statements in scripture on justification and both Paul and James reconcile with each other. There is no divide. There are no poles with which to side. Paul was making a comparison of Jesus to Adam, but that is not
only what he was doing. He was
also attributing the justification of the saint to the work of Jesus, not the work of the saint. One act of righteousness by Jesus leads to the justification (and life) for others (who did not commit the righteous act).
Note: I disagree with the definition of justification provided in Post 17. I know and accept that the definition provided is a commonly used one, but it is a theological definition, an extra-scriptural doctrinal definition, not the literal definition of the word as the NT writers used it. I can accept that definition for the purpose of this discussion (at least for the time being) but I make note this definition is a theologically doctrinal definition. Justification is a legal term. The Greeks used the term to simply mean standing or the possession of grounds sufficient to plead one's case. Strong's will tell use the word means to free or acquit, but the Greeks used the term to both guilty AND innocent. They applied it to those later exonerated AND those later found guilty. Justification simply means possessing grounds to stand before God in order to make ones case. Because the verdict on humanity had already been rendered (see John 3:18) no one had any grounds whatsoever to stand before God and plead their case. All had already been judged and all had already been condemned. Calvary changed that state of existence. Calvary provided a basis for a person to stand before God and plead his case. His case was,
"Father God, I stand before you covered in the shed blood of your resurrected Son without whom I could not stand before you."
There is no other case to present that saves. In order to present that case a person must first stand before God.
Bonhoeffer probably wasn't using the word in that way, but that does not change the fact that is what Paul meant. No one gets into the courtroom without having their robes washed white in the blood of Christ. The hearing has already been had. The judgment has already been rendered. Everyone has been condemned.
Court will open back up on sentencing day. We call it Judgment Day but John 3 makes it very clear the judgment has already been made. What we're really looking forward to is sentencing day, the day when God metes out the just recompense for sin. To those found in Christ grace is the sentence. To everyone else it's off to the fiery lake for destruction.
The declaration of righteousness is a declaration of a credited righteousness, not a righteousness the person justified possesses by his own doing. Leaving everything to follow Christ does not itself cause one to become righteous. It simply evidences the fact the declaration of righteousness is real, valid, and efficacious in one's life.
.