the believers are only those who believe in allah and his apostle then they doubt not and struggle hard with their wealth and their lives in the way of allah they are the truthful ones.
إنما المؤمنون الذين آمنوا بالله ورسوله ثم لم يرتابوا وجاهدوا بأموالهم وأنفسهم في سبيل الله أولئك هم الصادقون