Sayyiduna Abu Hurairah (may Allah be pleased with him) reports: He received this hadith of the Prophet (peace and blessings of Allah be upon him) that the Prophet (peace and blessings of Allah be upon him) said: "A strong believer is more beloved to Allah Almighty than a weak believer, though both are upon goodness. Strive for that which benefits you and do not become helpless. If something overcomes you, then say: This was the decree of Allah Almighty, and whatever He willed, happened. And avoid saying 'if' (i.e., saying: if this had happened, then that would have happened), for 'if' opens the door to the work of Satan."
Hadith Referenceصحیح ابن حبان / كتاب الحظر والإباحة / 5721
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «ظلال الجنة» (356): م.فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده حسن