I believe the idea is that since Jesus took all our sins on himself, he suffered all the punishment for those sins too - ie. eternal suffering times all the people who ever lived.
There is a certain logic to it if you squint really hard and turn your head in exactly the right way.
I don’t buy it myself.
I think it is exactly backwards. Jesus didn’t take our sins. We take his perfection. As a love gift from God.
Heh. Thanks.