123. Does God give the promise or guarantee of eternal life to all true believers in Christ?

the Bible Yes
Yes the Quran

the Bible's Perspective

John 3:16For God so loved the world, that he gave his only born Son, that whoever believes in him should not perish, but have eternal life.
John 3:36One who believes in the Son has eternal life, but one who disobeys the Son won’t see life, but the wrath of God remains on him.”
John 5:24“Most certainly I tell you, he who hears my word and believes him who sent me has eternal life, and doesn’t come into judgement, but has passed out of death into life.
John 10:28I give eternal life to them. They will never perish, and no one will snatch them out of my hand.
1 John 5:11He answered them, “He who made me well said to me, ‘Take up your mat and walk.’”

the Quran's Perspective

Ali 'Imran (House of Imran) 3:55(And remember) when Allah said: O Jesus! Lo! I am gathering thee and causing thee to ascend unto Me, and am cleansing thee of those who disbelieve and am setting those who follow thee above those who disbelieve until the Day of Resurrection. Then unto Me ye will (all) return, and I shall judge between you as to that wherein ye used to differ.
Ali 'Imran (House of Imran) 3:113-115They are not all alike. Of the People of the Scripture there is a staunch community who recite the revelations of Allah in the night season, falling prostrate (before Him). They believe in Allah and the Last Day, and enjoin right conduct and forbid indecency, and vie one with another in good works. These are of the righteous. And whatever good they do, they will not be denied the meed thereof. Allah is Aware of those who ward off (evil).
Al-Ma'ida (the Table spread) 5:47Let the People of the Gospel judge by that which Allah hath revealed therein. Whoso judgeth not by that which Allah hath revealed: such are evil-livers.
Al-Ma'ida (the Table spread) 5:69Lo! those who believe, and those who are Jews, and Sabaeans, and Christians - Whosoever believeth in Allah and the Last Day and doeth right - there shall no fear come upon them neither shall they grieve.

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