The Baháí calendar, also known as the Badí calendar, consists of 19 months of 19 days each. In between the 18th and 19th months, the Badí calendar incorporates 4-5 intercalary days, which do not constitute a part of any of the 19 months. These days are referred to as the ayyám-i-há, for the duration of which Bahá’u’lláh has enjoined bahá’ís to devote their time to celebration, good cheer, and charity. They are especially reserved for hospitality and the giving of gifts.
Following the intercalary days of the ayyám-i-há, the last month of the Badí calendar ensues, a month of fasting and restraint. During this month, adult bahá’ís fast, which entails abstaining from eating and drinking during certain times of the day. This month is essentially a period of meditation and prayer, of spiritual recuperation, during which a person should strive to make the necessary readjustments in his inner life, and to refresh and reinvigorate the spiritual forces latent in his soul. The significance and purpose of the Fast is therefore, fundamentally a spiritual one. Fasting is also a symbol, a reminder for abstaining from selfish and carnal desires. Naw-rúz (”New Day”) concludes the Fast, and is viewed as sign for ending the period of restraint, the inauguration of spring, and starting off the new year with renewed vigour and refreshment.