It is narrated marfu'an from Hazrat Hilb (may Allah be pleased with him) that such doubts should not arise in your hearts as the Christians were afflicted with, and you too begin to doubt like them.
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 21976
Hadith Gradingحکم دارالسلام:إسناده ضعيف، شريك سيئ الحفظ، لكنه توبع، وقبيصة مجهول، وقد اختلف فيه على سماك