If every sin was paid for at the cross, why do some people have to go to hell? If Jesus was punished for their sin, why must they also be punished? It seems like double jeopardy to me.
Hebrews 10:12 tells us that Jesus made one sacrifice for sin that’s good for all time, and according to Colossians 2:13-14 it’s also good for all our sins. Jesus said everyone who asks for salvation will receive it (Matt. 7:77-8), and Paul said everyone who calls on the name of the Lord will be saved (Romans 10:13).
These and other statements in the New Testament tell us salvation is a two step process. The Lord took one step for us by paying for all our sins. We have to take the other one by admitting we’re sinners, believing He died for our sins, and asking Him to save us.
By paying for everyone’s sins at once He made it possible for everyone to be saved no matter when we ask. If this was not the case, then every time someone asked the Lord for salvation He would have to be crucified all over again, because only His death can bring us eternal life.
It’s important to understand that people don’t go to Hell because they’re sinners. We’re all sinners. People go to Hell for not accepting the pardon the Lord provided for our sins. By not accepting His pardon they’re agreeing to pay for their own sins and that’s why they have to go to Hell.