“For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit:”
King James Version (KJV)
3:18 For - This is undoubtedly best, whereby we are most conformed to Christ. Now Christ suffered once - To suffer no more. For sins - Not his own, but ours. The just for the unjust - The word signifies, not only them who have wronged their neighbours, but those who have transgressed any of the commands of God; as the preceding word, just, denotes a person who has fulfilled, not barely social duties, but all kind of righteousness. That he might bring us to God - Now to his gracious favour, hereafter to his blissful presence, by the same steps of suffering and of glory. Being put to death in the flesh - As man. But raised to life by the Spirit - Both by his own divine power, and by the power of the Holy Ghost.
1Pe 3:18 For Christ also . . . suffered for sins. Even Christ, the Holy One, our example, once suffered on the cross. Once. Once only. He suffers no more. Being put to death in the flesh. He was put to death by the wounds inflicted on his fleshly body. His natural, earthly life was ended. Quickened in the spirit. Put to death in the body his spirit was quickened. Having life in himself, as soon as the body failed through weakness the power of the indestructible life began to show itself.