indeed the ones possessed of true faith are those who believed in allah and his messenger and then they did not entertain any doubt and strove hard in the way of allah with their lives and their possessions. these are the truthful ones.
إنما المؤمنون الذين آمنوا بالله ورسوله ثم لم يرتابوا وجاهدوا بأموالهم وأنفسهم في سبيل الله أولئك هم الصادقون