"Let none of you suffer as a murderer or a thief or an evildoer or as a meddler. Yet if anyone suffers as a Christian, let him not be ashamed, but let him glorify God in that name. For it is time for judgment to begin at the household of God; and if it begins with us, what will be the outcome for those who do not obey the gospel of God? And “If the righteous is scarcely saved, what will become of the ungodly and the sinner?” Therefore let those who suffer according to God's will entrust their souls to a faithful Creator while doing good." (1 Peter 4:15-19)
This is talking about suffering in the flesh. Certainly Christ did not "barely save us" in the sense of rebirth. The judgement in focus here isn't God's judgement on His people but a judgment, condemnation, & persecution from the secular world upon Christians. God's people are barely saved in the flesh from such oppressive rule & perhaps aren't saved at all. This entire context is about Christians suffering for doing good rather than suffering for doing bad.
Peter is saying, "Please don't commit crimes, if you are going to suffer only let it be for doing God's good. God in His mercy can barely save you righteous people from punishment handed out by the government because He can't override people's freewill & wicked people aren't going to cooperate with Him. Think about those who actually do wrong & don't know God. God can't always get you off the hook so don't intentionally put yourself on the hook by committing crimes. When you know you are going to suffer for doing good entrust your soul (earthly life) to God so you won't fear regardless of the outcome."
Peter concludes his letter & writing about suffering by saying it is the devil who seeks to harm you, not God. God is love & He does not punish His children. He cares for us.
"Cast all your anxieties on God, because he cares for you. Be sober-minded; be watchful. Your adversary the devil prowls around like a roaring lion, seeking someone to devour. Resist him, firm in your faith, knowing that the same kinds of suffering are being experienced by your brotherhood throughout the world. And after you have suffered a little while, the God of all grace, who has called you to his eternal glory in Christ, will himself restore, confirm, strengthen, and establish you." (1 Peter 5:7-10)
The reason why "judgement" (this particular word is sometimes translated as condemnation) starts at the household of God is because Satan hates the people of God so he is going to influence rulers & oppressors to oppress them. Oppressors want to oppress just about everyone but Satan makes Christians a focal point of theirs. Physical persecution is Satan's last resort to harm the house of God. In western Christianity Satan doesn't need to physically persecute Christians. Because of 100s to 1,000s of years of religious teachings Christians condemn themselves. The problem with western Christians isn't that they "should do more for God" it is that they believe the wrong things about themselves & God. So Satan doesn't need to devour them. They consume themselves with guilt, shame, & fear all based on a false idea of God & a false idea of themselves.