It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) said: "Modesty beautifies whatever it is in, and indecency makes whatever it is in ugly."
Hadith Referenceالادب المفرد / كتاب / 601
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : أخرجه الترمذي ، كتاب البر و الصلة، باب ما جاء فى الفحش : 1974 و ابن ماجه : 4185 - انظر المشكاة : 4854»
Explanation & Benefits
Shaykh Maulana Usman Muneeb
Benefits and Issues: Modesty (haya) is the adornment of a Muslim, through which his personality appears beautiful. In some narrations, gentleness has been described as the beauty of character, which means that only a person with a gentle temperament can be truly modest. A harsh-tempered and severe-natured person cannot possess modesty. Thus, modesty necessitates gentleness, and gentleness necessitates modesty. Foul language and immodesty can distort even the greatest of characters; therefore, one should strive to cultivate modesty within oneself. In particular, scholars should certainly avoid conversations that are contrary to dignity and based on obscenity.
Source: Fadlullah al-Ahad: Urdu Commentary on al-Adab al-Mufrad, Page: 601