Amir'ul-Mu'mineen ‘Ali (as) says that Allah is Magnificent and likes beauty and charm. Therefore, taking care of one's own person is a good act.
Imam Ja'far As-Sadiq (as) says that when Allah has bestowed a person with good personality, he must make it visible! He should take care of his person that the angels say, ‘this is Allah's friend who is expressing gratitude to Allah by manifesting the good personality endowed to him!' If the person behaves contrary to the above, the angels would say, ‘The person is Allah's enemy. He is hiding his personality and is taking Allah's blessing for granted!'
It is narrated from authentic sources that Sufian Suri saw Imam Ja'far As-Sadiq (as) at the mosque dressed in expensive raiment. He went near the Imam (as) and said, "O son of the Prophet (S)! Your ancestor, the Prophet (S), never wore such expensive clothes!" The Imam (as) replied, "Yes! That was the time when the Muslims were impecunious and the common man did not afford good clothes. The Prophet (S) didn't want to wear expenses clothes to respect the feelings of the people. Now the times have changed and the people are prosperous to afford good clothes. In these circumstances the Imam (as) cannot wear sub-standard clothes!"
Then the Imam (as) drew Sufian Suri nearer to himself and said, "Do you think I am wearing these clothes to satisfy my ego?" Then he removed his expensive clothes and showed to him the less than ordinary clothes he was wearing beneath the expensive dress, and said, "This is the dress that I wear to satisfy my conscience while the outer garment is for the view of the common people." Saying this, he drew aside Sufian Suri's dress and showed him the garment he was wearing inside, that was much more expensive than the outer garment. Then the Imam (as) said, "This is your clothing you wear to satisfy your ego and the inexpensive clothing you wear as outer garment is to show to the people that you are frugal in your habits! This is sheer deception that people consider you a pious person!"
About Elegance and Adornment
When Amir'ul-Mu'mineen ‘Ali (as) deputed Abdallah bin Abbas to visit the Khawarij (the Dissenters) to make the final presentation about the Imam (as)'s authenticity (Hujjat), Abdallah was dressed in expensive raiment and wore fragrant perfume. He was astride a high quality steed. The Dissenters protested, "O Abdallah! Why are you dressed like the despots?" In reply Abdallah recited this verse from the Qur'an, "Adornment with Halal and pure earning is not Haram (taboo)" (7:32)
Imam Ja'far As-Sadiq (as) always used to wash new clothes before wearing them. He said, "Wear decent dress and adorn yourselves with the gifts of Allah!"
Imam Zain-ul-'Abidin (as) used to wear a robe worth five hundred and a shawl worth fifty Dinars. After the winter season he used to sell the dress and give the proceeds to the poor in alms. Similarly the dress he wore during the summers, he would sell at the end of the season and give the money to the poor and needy.
It comes in the traditions that Allah likes people adorning themselves well. He doesn't like people to give appearance of penury and shabbiness. Someone asked the Prophet (S), "How should one manifest the Blessings of Allah?" He said, "Adorn yourselves with good dress, wear decent perfume, keep your dwelling clean and tidy, at sunset light a lamp in your house. This way penury and hunger escape from you. Prosperity will come to you!"
Rabi bin Ziyad complained to Amir'ul-Mu'mineen ‘Ali (as) in Basra about his brother Asim bin Ziyad that he had abandoned his children and become a recluse, dressing like a beggar! Amir'ul-Mu'mineen ‘Ali (as) called Asim and told him, "O enemy of your soul! The Satan has led you astray! You have no mercy on your family and children? Do you think that Allah has made His legitimate Blessings taboo (Haram) for you? Allah is the Greatest and would not put you to such unnecessary hardship.
Therefore He says in the Holy Qur'an, "And He made the land for His creatures which has fruits and date palms having covers over their bunches. (Sura Rahman, 55:10-11)" Then the Imam (as) continued, "He made two rivers flow that meet (at a confluence) They have a boundary between them from which they cannot exceed. From them pearls and oysters come out."
Using the Bounties of Allah by His creatures is dear to Him. He likes men to thank him too for His Bounties. He says, "And keep talking about Allah's Blessings" Aasim said, "O Imam (as)! Then why do you content yourself with dried bread and coarse clothing?" The Imam (as) replied, "O Aasim! I am unlike you! Allah has made it obligatory on us to live like the poor and the needy that they don't become conscious of their penury! When they see their Imam (as) in that condition, they would resign to their own fates!" Hearing this, Aasim reverted back to his former habits. If Allah has given fair means to a person, he should make good use of them for himself and help the poor and needy to the extent possible.
Imam Ja'far As-Sadiq (as) said that Allah will take account of three things from all the humans: firstly, the food that a person consumed, secondly, the dress that the person had used thirdly, the help the person had given to others with good intent, The Prophet of Allah (S) has said, "O Abu Dharr! If Allah gives good raiment to a person, he should wear it! If He gives coarse clothing, the person should be content with it. Man should be grateful to Allah under all circumstances."
source : www.imamreza.net