But God demonstrates his own love for us in this: While we were still sinners, Christ died for us. (NIV)

But God shows and clearly proves His [own] love for us by the fact that while we were still sinners, Christ (the Messiah, the Anointed One) died for us. (AMP)

But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us. (KJV)