Pain for God's Sake

Thaipusam is a Hindu festival celebrated mostly by the Tamil community.

Devotees prepare for the celebration by cleansing themselves through prayer and fasting. Kavadi-bearers have to perform elaborate ceremonies at the time of assuming the kavadi and at the time of offering it to Murugan. The kavadi-bearer observes celibacy and take only pure, Satvik food, once a day, while continuously thinking of God.

On the day of the festival, devotees will shave their heads and undertake a pilgrimage along a set route while engaging in various acts of devotion, notably carrying various types of kavadi (burdens). At its simplest this may entail carrying a pot of milk, but mortification of the flesh by piercing the skin, tongue or cheeks with vel skewers is also common.

The simplest kavadi is a semicircular decorated canopy supported by a wooden rod that is carried on the shoulders, to the temple. In addition, some have a small spear through their tongue, or a spear through the cheeks. The spear pierced through his tongue or cheeks reminds him constantly of Lord Murugan. It also prevents him from speaking and gives great power of endurance. Other types of kavadi involve hooks stuck into the back and either pulled by another walking behind or being hung from a decorated bullock cart or more recently a tractor, with the point of incisions of the hooks varying the level of pain. The greater the pain the more god-earned merit.

source: Wikipedia