Romans 5:8, “But God demonstrates His love toward us, that in our still being sinners Christ died for us.”
This is a comparison with the verse before. Paul understood the general rule to be that someone might die for a friend, but not for someone they weren’t friends with. However, God proves His love (the love that has been poured out on us, v. 5) for us by giving up His life on our behalf, even when we were His enemies. This is love of the highest kind.