Iman resides in our heart and it's naked, prone to damage and harm, we need Taqwa to clothe our heart so that it's not affected, and we need Haya to beautify it and adorn it.
Allah Subḥānahu wa-taʿālā says in the Qur’an - “O children of Adam, We have bestowed upon you clothing to conceal your private parts and as adornment. But the clothing of righteousness - that is best. That is from the signs of Allah that perhaps they will remember”
No one is perfect, we all have sins, which only Allah Subḥānahu wa-taʿālā knows about and the garment of Taqwa clothe our hearts. This garment of Taqwa covers our weaknesses, shielding us from the eyes of others in this dunya and also safeguards us from the wrath of Allah.
We all will be resurrected naked; then everyone will be clothed according to the level of our faith; this is our Libaas. All of us will have to stand before Allah; imagine meeting Allah while adorned with a beautiful gown. We must take care of the fabric of our faith to keep it from being damaged. It can get torn because of our sins. It can also acquire loose threads, as our faith decreases, which might unravel the whole cloth, leaving us with nothing.
And the Distinctive Characteristic with which we are known is al-Hayaa’ this beautifies our Libaas, i.e Taqwa. And it is given so much importance, because al-Hayaa’ is good and it only brings good, and al-Hayaa’ is not present in a thing except that it beautifies it.
Taqwa and Haya are from the good character of the heart and from the actions of the heart. Shyness, modesty, and a conscious heart prevents a person from that which is unbefitting and wrong.
The one whom Allāh has blessed and nourished with Haya is prevented from vile behavior and evil conduct - and he is distinguished with fine attributes and feels shy to commit indiscretions against His Lord. Haya, therefore, is good and its absence is a deficiency and shortcoming.
Whoever’s Hayaa’ (modesty/shyness) decreases, his religiosity decreases. And he who’s religiosity decreases, his heart dies.
[at-Tabaraani ( raḥimahu -llāh ) in al-Awsat, 2/370 and al-Bayhaqi in Shu’b al-Eemaan, 7/59]
Ibn Rajab (raḥimahu -llāh) said: Some of the Salaf used to say:
Whoever has Taqwa, Allaah Subḥānahu wa-taʿālā has surely preserved his own self,
While the one who loses Taqwa of Allah Subḥānahu wa-taʿālā has only lost himself,
And Allah Subḥānahu wa-taʿālā is not in need of him!
Have we made ourselves worthy in the sight of Allah ?
O woman of Jannah, may Allah fragrance your life with knowledge and Eman, your time with obedience and awareness of Him and may He beautify your body with covering and modesty…Ameen