It is narrated from Sayyiduna Abu Huraira (may Allah be pleased with him) that the Messenger of Allah (peace and blessings of Allah be upon him) said: "A believer (regarding worldly matters) is simple-hearted and noble in character, whereas a disbeliever and a hypocrite is deceitful, wicked, and mean."
Hadith Referenceالادب المفرد / كتاب / 418
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : أخرجه أبوداؤد ، كتاب الأدب ، باب فى حسن العشرة : 4790 و الترمذي : 1964 - انظر صحيح الترغيب : 2609»
Explanation & Benefits
Shaykh Maulana Usman Muneeb
Benefits and Issues: ➊ The outward and inward states of a believer are the same. What he utters with his tongue, his heart also affirms. He does not delve into excessive scrutiny in worldly matters, nor does he try to become aware of people’s inner conditions; rather, he trusts people, having good thoughts and a positive opinion about them. This is not due to his ignorance, but because of the purity of his heart and mental cleanliness—he considers others to be like himself. However, in matters of the Hereafter, he is courageous and very alert. He remains vigilant for the betterment of his Hereafter and does not display laziness or sluggishness. In a hadith, such people are described as the wisest and most intelligent. The statement of the Prophet (sallallahu alayhi wa sallam) is: ((The best of the believers is the one with the best character, and the wisest among them is the one who remembers death the most and prepares for it in the best manner. These are truly the intelligent ones.)) (Al-Sahihah by Al-Albani, Hadith: 1384) ➋ The outward and inward states of the hypocrite and the disbeliever are different. He cunningly spies on people and tries to create corruption. He does not overlook even a slip of his companion, let alone forgive an enemy. He can stoop to the lowest acts for this purpose, while in matters of the Hereafter, he is extremely lazy and useless. ➌ By “fajir” here, what is meant is not a sinful Muslim, but rather a disbeliever and a hypocrite.
Source: Fadlullah al-Ahad: Urdu Commentary on al-Adab al-Mufrad, Page: 418