13. Are believers allowed to believe in one part of the Scripture while disbelieving in another part of Scripture?

the Bible No
No the Quran

the Bible's Perspective

Joshua 1:8This book of the law shall not depart from your mouth, but you shall meditate on it day and night, that you may observe to do according to all that is written in it; for then you shall make your way prosperous, and then you shall have good success.
Acts 20:27for I didn’t shrink from declaring to you the whole counsel of God.
1 Timothy 4:13-15Until I come, pay attention to reading, to exhortation, and to teaching. Don’t neglect the gift that is in you, which was given to you by prophecy with the laying on of the hands of the elders. Be diligent in these things. Give yourself wholly to them, that your progress may be revealed to all.
2 Timothy 3:16Every Scripture is God-breathed and profitable for teaching, for reproof, for correction, and for instruction in righteousness,

the Quran's Perspective

Al-Baqara (The Cow) 2:85Yet ye it is who slay each other and drive out a party of your people from their homes, supporting one another against them by sin and transgression? - and if they came to you as captives ye would ransom them, whereas their expulsion was itself unlawful for you - Believe ye in part of the Scripture and disbelieve ye in part thereof? And what is the reward of those who do so save ignominy in the life of the world, and on the Day of Resurrection they will be consigned to the most grievous doom. For Allah is not unaware of what ye do.
Al-Baqara (The Cow) 2:136Say (O Muslims): We believe in Allah and that which is revealed unto us and that which was revealed unto Abraham, and Ishmael, and Isaac, and Jacob, and the tribes, and that which Moses and Jesus received, and that which the prophets received from their Lord. We make no distinction between any of them, and unto Him we have surrendered.
Al-Baqara (The Cow) 2:285The messenger believeth in that which hath been revealed unto him from his Lord and (so do) believers. Each one believeth in Allah and His angels and His scriptures and His messengers - We make no distinction between any of His messengers - and they say: We hear, and we obey. (Grant us) Thy forgiveness, our Lord. Unto Thee is the journeying.
Ali 'Imran (House of Imran) 3:84Say (O Muhammad): We believe in Allah and that which is revealed unto us and that which was revealed unto Abraham and Ishmael and Isaac and Jacob and the tribes, and that which was vouchsafed unto Moses and Jesus and the prophets from their Lord. We make no distinction between any of them, and unto Him we have surrendered.
Ali 'Imran (House of Imran) 3:119Lo! ye are those who love them though they love you not, and ye believe in all the Scripture. When they fall in with you they say: We believe; but when they go apart they bite their finger-tips at you, for rage. Say: Perish in your rage! Lo! Allah is Aware of what is hidden in (your) breasts.

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