“Arm yourselves with the same thought,” that is, with the thought of sufferings. Be ready to endure sufferings for Christ, as He suffered for us. Endure them if God is pleased to send them upon you.
Let the disciple become like the Teacher.
“Arm yourselves.” This word points to struggle and warfare, of course against the temptation of the opposite thought. This thought draws sinful man, for whom sufferings are hard, to avoid sufferings in one way or another.
Therefore it is truly necessary to arm oneself precisely with the thought of Christ’s sufferings, in order to overcome the thought of avoiding sufferings.
“For he who suffers,” more precisely, “he who has suffered,” “in the flesh ceases,” more precisely, “has ceased,” “from sin.” At first glance this is a general thought.
Its meaning would be that bodily sufferings weaken the power and action of human sinfulness and help sin to cease. The sufferer sins less, or at least ceases to sin in the same measure as he sinned when he was not suffering.
But this thought is expressed too strongly, decisively, and unconditionally, especially in the original. It therefore compels one to seek a more definite meaning.
Such a meaning can be found by comparing this saying with similar ones in the holy apostle Paul. According to his teaching, the man who turns to Christ by faith in His redemptive death on the Cross is crucified with Him.
By baptism into Christ’s death, he is buried with Him. The one who has died is freed from sin. Therefore a Christian must reckon himself dead to sin.
This means that sin must no longer rule over him, and he must not be a slave of sin (Rom 6:1-23).
It seems that this very teaching is briefly expressed in the saying of the apostle Peter under consideration. Thus the entire sixth chapter of Romans serves precisely as its interpretation.
The apostle Peter also speaks of the believer’s co-crucifixion with Christ: “arm yourselves with the same thought.” He also speaks of the saving power of baptism through Christ’s resurrection (1 Pet 3:21).
That resurrection was preceded by His death, into which, according to the apostle Paul, the believer in Him is baptized. Thus he dies with Christ.
The one who has died is freed from sin and must walk in virtues by a renewed, as it were risen, life. He must be a slave not of sin unto death, but of righteousness unto eternal life.
This thought is expressed briefly in the saying of the apostle Peter under consideration. It may be paraphrased in this way.
You Christians were crucified with Christ in sufferings and died with Him in baptism. Consequently, you died to sin, for the one who has died is freed from sin and has ceased to sin.
The one who has suffered in the flesh, as Christ suffered in the flesh, and who died with Him in baptism, has ceased from sin. He must now live according to the will of God, and not according to human desires (verse 2).