Ihram

Ihram (إحرام iḥrām, from the triconsonantal root Ḥ-R-M) is, in Islam, a sacred state which a Muslim must enter in order to perform the major pilgrimage (Hajj) or the minor pilgrimage (Umrah). A pilgrim must enter into this state before crossing the pilgrimage boundary, known as Miqat, by performing the cleansing rituals and wearing the prescribed attire.

A man in the state of Ihram must not tie any knots or wear any stitched items. Sandals and flip flops must not be stitched either and should allow the ankle and back of foot to be exposed (some other schools of thought also agree that the front of the foot must be shown as well). Whilst in the state of Ihram, a Muslim must not use any scents on the body or on the robes. If the robe has been fouled by najas (dirty) material or has been wiped, rubbed or touched by scented liquids (intentionally), then a new iḥrām clothing must be worn, or the Umrah or Hajj will be invalid.

During ihram, women must have their faces uncovered; they are forbidden to wear the Burqa or Niqab. However, the Hijab or Dupatta is obligatory. There is also no gender segregation during the Hajj. Unlike in mosques, men and women pray together, not just in the same area but also on the same prayer line. This is to remind everyone that on the Day of Judgment, both men and women will be standing together, side by side, in the same rows.

Aside from being as clean (purified) as they are for prayer, male Muslims are expected to refrain from cutting their nails, and trimming their hair and beards. They must also not wear any scent, including deodorant. They have to wear Ihram clothing, which is a white, seamless garment. Many also shave their head as this is considered hygienic. Most will wait to shave their heads until after they have finished Umrah or Hajj, as this is a requirement to leave the state of Ihram. Female Muslims are also expected to be clean. During the pilgrimage, sexual activity, smoking and swearing are also forbidden.

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Wikipedia