The One Whose Garment hangs down below His Ankles is a Sinner, but His Prayer is Correct

Question :

What is the ruling on praying in a garment which covers the ankles, and is prayer behind one who wears such a garment correct, even though this person knows the Hadiths which prohibit it? Inform us, and may Allah reward you with goodness.

Answer:

The prayer of one whose garment hangs below his ankles is correct, but he is guilty of sin, and he must be advised and warned against that which Allah has forbidden.

It is an obligation upon the Muslim to make sure that his clothing does not hang down below his ankles, as the Prophet said:

"Whatever hangs down below the ankles from the Izar will be in the Hell-Fire.

The ruling on all clothes including long shirts, trousers and cloaks is the same as that of the Izar. It has been authentically reported from the Messenger of Allah that he said:

There are three to whom Allah will not speak on the Day of Resurrection, nor will He look at them, nor will He purify them, and upon them is a painful punishment: The one who lets his garments trail, Al-Mannan, and the one who sells his wares by falsely swearing about them.

That is regarding the duty upon men; as for the woman, she must cover her feet with socks when she goes out to the market, or use a long, flowing dress. Likewise, in the house, if there are any non-blood related men present, such as her brother-in-law or the like. And through Allah is attained success.

Source:
Ibn Baz
Fatawa Islamiyah, Vol. 2 Pages 227-228