"For Christ also died for sins once for all, the just for the unjust, so that He might bring us to God, having been put to death in the flesh, but made alive in the spirit." (1 Peter 3:18)Suffering is permitted for many reasons. Sometimes it is for ourselves, to purify our souls and make us more like Christ, sometimes it is for Christ, to bring Him glory and honor, and sometimes it is for other people. Jesus told us, "A disciple is not above his teacher, nor a slave above his master. It is enough for the disciple that he become like his teacher, and the slave like his master." (Matthew 10:24-25) Much of the suffering of Jesus was for our sake, He died for us that we might live, He became sin on the cross that we might be forgiven, He became weak that we might become strong. In the same way, it is for us to be like our teacher and suffer for the benefit of others. Paul understood this and suffered much for the sake of the elect. Speaking to Timothy he said, "Remember Jesus Christ... for which I suffer hardship even to imprisonment as a criminal; but the word of God is not imprisoned. For this reason I endure all things for the sake of those who are chosen, so that they also may obtain the salvation which is in Christ Jesus and with it eternal glory." (2 Timothy 2:8-10) Paul gladly endured much suffering, not because it was to his own benefit, but because it was to the benefit of others, that they too might obtain in Christ what he had also obtained. Jesus suffered for us, and yet, there still remains something lacking in His suffering. Paul says, "Now I rejoice in my sufferings for your sake, and in my flesh I do my share on behalf of His body, which is the church, in filling up what is lacking in Christ's afflictions." (Colossians 1:24) Jesus suffered in the flesh and there yet remains some suffering to be accomplished for the sake of those being saved. As we are His body and His flesh on the earth, it remains for us to full up what is lacking in Christ's suffering. This almost sounds sacrilege, but it is still our responsibility. How different might we view our sufferings if we understood that we were performing the sufferings of Christ and suffering for the sake of others?
"in which also He went and made proclamation to the spirits now in prison, who once were disobedient, when the patience of God kept waiting in the days of Noah, during the construction of the ark, in which a few, that is, eight persons, were brought safely through the water." (1 Peter 3:19-20)
Prior to the Law, men still sinned and died even through there was not direct law they were transgressing. Paul writes on this topic, "Therefore, just as through one man sin entered into the world, and death through sin, and so death spread to all men, because all sinned — for until the Law sin was in the world, but sin is not imputed when there is no law. Nevertheless death reigned from Adam until Moses, even over those who had not sinned in the likeness of the offense of Adam, who is a type of Him who was to come." (Romans 5:12-14) Jesus, after His death descended into Sheol, or Hades, to speak the Gospel to those who had sinned in the past, but not in the likeness of Adam by transgressing a specific commandment of God. Jesus didn't descend into Hell, as far as I can tell no one is there yet, it is in reserve for the final judgment, but He descended into Hades, the place of departed spirits who await the judgment of the final end. Upon His resurrection, it is said that, "the graves were opened; and many bodies of the saints who had fallen asleep were raised; and coming out of the graves after His resurrection, they went into the holy city and appeared to many." (Matthew 27:52-53 NKJV) It appears that many believed Him and received His resurrection power. I think this is what it means when it was said of Jesus, "When He ascended on high, He led captivity captive." (Ephesians 4:8 NKJV)
"Corresponding to that, baptism now saves you — not the removal of dirt from the flesh, but an appeal to God for a good conscience — through the resurrection of Jesus Christ, who is at the right hand of God, having gone into heaven, after angels and authorities and powers had been subjected to Him." (1 Peter 3:21-22)
Peter is making a reference back to the flood and the Arc of Noah saying it is a type of the salvation purchased for us by Jesus. The waters of baptism are like the waters of the flood; separating the former world from the new world, separating our past life from our new life. When we go through baptism, there is an appeal to God for a life that is better, a life that is holy, just like there was an appeal to God for a better world than existed before the flood, a world where every thought and intent of man was evil. "Then the Lord saw that the wickedness of man was great on the earth, and that every intent of the thoughts of his heart was only evil continually." (Genesis 6:5) Our baptism stands between our old life of sin and our new life that is created in righteousness. We enter baptism as one already dead and emerge with a new life. "Therefore we have been buried with Him through baptism into death, so that as Christ was raised from the dead through the glory of the Father, so we too might walk in newness of life." (Romans 6:4) How blessed we are for His salvation and this new life He has given us!