Hair is not customarily cropped or trimmed in Sikhism. Sikhs believe that hair is a gift from God and that it should not be altered. However, if someone is sick or has an accident then hair may be cut.
Sikhs believe that the only true sacred hair is that of the Prophet Muhammad. All other human hair is considered profane and should not be worn as jewelry or used for clothing. The only exception to this rule is when a person is mourning the loss of their own hair, at which time any kind of hair is acceptable.
In some cases, especially with young children, parents will cut their child's hair in order to make them more comfortable. This is also common among female inmates who have been denied visitation rights because they cannot provide an adequate security risk assessment. These practices are not supported by Sikh tradition but rather than cause further alienation from family members, it is more likely that they would simply be ignored.
Sikhs honor God's gift of hair by not cutting it. Kesh is so significant that during the Mughal Empire's persecution of Sikhs, followers were ready to face death rather than shave or trim their hair to disguise themselves. The people are religious, and not cutting their hair is/was a symbol of their benevolence.
Punjabis wear their hair long because that is how the gods decreed it. Not cutting your hair is an act of reverence - you are acknowledging that what you are given is perfect as it is. This idea comes from the Sikh belief that god created our physical form as well as our minds, so it is important to respect both.
In the 18th century, the Mughals made shaving against religion punishable by death. This fear of punishment kept many Sikh masters from cutting their students' hair, which led to a decline in quality of education. When Guru Gobind Singh Ji founded the Khalsa in 1699, he allowed its members to cut their hair, which immediately made it acceptable in his eyes. Nowadays, most Sikhs allow their hair to grow out because there is no longer any danger of being punished for not cutting it.
Carrying lengthy hair is difficult. According to our guru's Rehat Maryada (living rules), a Sikh shall never trim any hair from any area of the body. Sikh males are now shaving their beards and cutting their hair, and Sikh women are choosing for threading, waxing, haircuts, and so on. These actions are not allowed by the Guru's rules.
Beard and hair growth is a sensitive issue for many people. Some men feel that if they cannot see a Sikh's beard or hair, then they are not looking too closely. But the truth is that even though they may not be able to see a beard or hair, others can. It's important to understand that just because you cannot see something, this does not mean that it is not there. Be aware of what other people are doing or not doing so as not to cause offence.
As a general rule, beard and hair length should be suitable for religious observance. If you would like to shave your beard or hair, please do so during periods of relaxation and contemplation. This will allow you to make an informed decision and not do anything out of haste or anger.
A Sikh who shaves his beard or cuts his hair has abandoned his holy garment. Thus, such a person cannot again become a disciple until he or she repents for having done so. Even after repentance, one's father's name cannot be used to initiate the new disciple into the community.