Kathina marks the end of the rains retreat (Vassa). On this occasion, lay devotees come together to offer robes to the community of monks (Sangha) who have spent the vassa at a particular monastery, meditation centre or some other dwelling place.

The offering of the Kathina robe started during the time of the Buddha. After observing the three months rains retreat,some monks were on their way to the monastery at Savatthi where the Buddha was staying. They were drenched and soaked to the skin by a heavy downpour when they reached the destination. Taking into consideration their condition, the Buddha prescribed a Kathina ceremony to be performed by monks when they have completed their rains retreat.

It is the custom of Theravada Buddhists to participate in the ceremony with the offering of robes and/or other requisites. The distribution of the robes received by the monks from the lay devotees are entirely a matter of the Sangha members. The Kathina ceremony promotes the interdependency between the Sangha and the laity. The offerings, made through the devotees natural desire to support the Sangha, is an important merit-making event for Theravada Buddhists.