All Christians will Believe in Eesa Before He Dies
In this ayah Allah subhanahu wa ta’ala said,
وَإِن مِّنْ أَهْلِ الْكِتَـبِ إِلاَّ لَيُؤْمِنَنَّ بِهِ قَبْلَ مَوْتِهِ وَيَوْمَ الْقِيَـمَةِ يَكُونُ عَلَيْهِمْ شَهِيداً
“And there is none of the People of the Scripture, but must believe in him, before his death. And on the Day of Resurrection, he will be a witness against them.”
This can be taken in two ways; one when a Christian dies the angel of death tells him about the reality of Prophet Eesa aalyhi salaam. Ibn Jareer recorded that Ibn Abbas radhiAllahu anhu commented that this means that when Prophet Eesa aalyhi salaam returns, he won’t die until all the Christians of that time have accepted him as a Messenger and not the son of God.