Is it impermissible for a man to pray whilst his hair is tied together; for example with an elastic band ?
See the following fatwa of The Permanent Committee for Scholarly Research and Ifta’ :
Q 1: Concerning the Hadith: “I have been commanded not to tuck up the cloth or hair.” which prohibits folding clothes. Does the Hadith apply to those who roll their trousers up claiming they apply the Sunnah though the Hadith includes prohibition?
A: The Hadith indicates that a person offering Salah should not busy himself and mess with his clothes and hair during Salah (Prayer), or prevents the ends of his clothes from reaching the ground when prostrating. In fact, the person offering Salah should leave his clothes come down with him, and should not braid his hair but should untie it so that it prostrates with him.
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.
The Permanent Committee for Scholarly Research and Ifta’