(Rom 11:32) “For God hath concluded them all in unbelief, that he might have mercy upon all.” Unbelief therefore is sin; enough of a sin to send anyone to hell for eternity: (Jas_2:10) “For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all.” Therefore the Lord Jesus bore the sins of all that He might have mercy upon each of us who repent and ask for mercy.