The Báb introduced a new calendar, known now as the Badí or Bahá'í calendar (see notes 27 and 147). According to this calendar, a day is the period from sunset to sunset. In the Bayán, the Báb ordained the month of `Alá to be the month of fasting, decreed that the day of Naw-Rúz should mark the termination of that period, and designated Naw-Rúz as the Day of God. Bahá'u'lláh confirms the Badí calendar wherein Naw-Rúz is designated as a feast.

Naw-Rúz is the first day of the new year. It coincides with the spring equinox in the northern hemisphere, which usually occurs on 21 March. Bahá'u'lláh explains that this feast day is to be celebrated on whatever day the sun passes into the constellation of Aries (i.e. the vernal equinox), even should this occur one minute before sunset (Q and A 35). Hence Naw-Rúz could fall on 20, 21, or 22 March, depending on the time of the equinox.

Bahá'u'lláh has left the details of many laws to be filled in by the Universal House of Justice. Among these are a number of matters affecting the Bahá'í calendar. The Guardian has stated that the implementation, worldwide, of the law concerning the timing of Naw-Rúz will require the choice of a particular spot on earth which will serve as the standard for the fixing of the time of the spring equinox. He also indicated that the choice of this spot has been left to the decision of the Universal House of Justice.

-- The Kitab-i-Aqdas, Notes, No. 26

The 12-day Festival of Ridvan commemorates Baha'u'llah's public declaration of His mission in the Garden of Ridvan in Baghdad in 1863. The first, ninth and twelfth days are regarded as particularly holy.

Say: The Most Great Festival is, indeed, the King of Festivals. Call ye to mind, O people, the bounty which God hath conferred upon you. Ye were sunk in slumber, and lo! He aroused you by the reviving breezes of His Revelation, and made known unto you His manifest and undeviating Path.

-- Bahá'u'lláh, The Kitab-i-Aqdas

This is a reference to the arrival of Bahá'u'lláh and His companions in the Najíbíyyih Garden outside the city of Baghdád, subsequently referred to by the Bahá'ís as the Garden of Ridván. This event, which took place thirty-one days after Naw-Rúz, in April 1863, signalized the commencement of the period during which Bahá'u'lláh declared His Mission to His companions. In a Tablet, He refers to His Declaration as "the Day of supreme felicity" and He describes the Garden of Ridván as "the Spot from which He shed upon the whole of creation the splendours of His Name, the All-Merciful". Bahá'u'lláh spent twelve days in this Garden prior to departing for Istanbul, the place to which He had been banished. The Declaration of Bahá'u'lláh is celebrated annually by the twelve-day Ridván Festival, described by Shoghi Effendi as "the holiest and most significant of all Bahá'í festivals" (see notes 138 and 140). -- The Kitab-i-Aqdas

21 April First Day of Ridvan.

29 April Ninth Day of Ridvan

2 May Twelfth Day of Ridván

23 May Declaration of the Bab. The Bab was the forerunner of Baha'u'llah. This day marks the anniversary of the Bab's declaration of His mission in 1844.

The Promulgation of Universal Peace, p. 138 `Abdu'l-Bahá

This is 23 May, the anniversary of the message and Declaration of the Báb. It is a blessed day and the dawn of manifestation, for the appearance of the Báb was the early light of the true morn, whereas the manifestation of the Blessed Beauty, Bahá'u'lláh, was the shining forth of the sun. Therefore, it is a blessed day, the inception of the heavenly bounty, the beginning of the divine effulgence. On this day in 1844 the Báb was sent forth heralding and proclaiming the Kingdom of God, announcing the glad tidings of the coming of Bahá'u'lláh and withstanding the opposition of the whole Persian nation. Some of the Persians followed Him. For this they suffered the most grievous difficulties and severe ordeals. They withstood the tests with wonderful power and sublime heroism. Thousands were cast into prison, punished, persecuted and martyred. Their homes were pillaged and destroyed, their possessions confiscated. They sacrificed their lives most willingly and remained unshaken in their faith to the very end. Those wonderful souls are the lamps of God, the stars of sanctity shining gloriously from the eternal horizon of the will of God.

29 May Ascension of Baha'u'llah. This day marks the passing of Baha'u'llah in 1892.

From The Promulgation of Universal Peace, p. 28
'Abdu'l-Baha

The Blessed Perfectin was a prisoner twenty-five years. During all this time he was subjected to the indignities and revilements of the people. He was persecuted, mocked and put in chains. ...

During His lifetime He was intensely active. His energy was unlimited. Scarcely one night was passed in restful sleep. He bore these ordeals, suffered these calamities and difficulties in order that a manifestation of selflessness and service might become apparent in the world of humanity, that the Most Great Peace should become a reality, that human souls might appear as the angels of heaven, that heavenly miracles would be wrought among men; that human faith should be strengthened and perfected; that the precious, priceless bestowal of God -- the human mind -- might be developed to its fullest capacity in the temple of the body; and that man might become the reflection and likeness of God, even as it hath been revealed in the Bible, 'Let us make man in our image.'

Briefly, the Blessed Perfection bore all these ordeals and calamities in order that our hearts might become enkindled and radiant, our spirits be glorified, our faults become virtues, our ignorance be transformed into knowledge; in order that we might attain the real fruits of humanity and acquiree heavenly graces; in order that, although pilgrims upon earth, we should travel the road of the heavenly kingdom, and although needy and poor, we might receive the treasures of eternal life. For this has He borne these difficulties and sorrows.

9 July Martyrdom of the Bab. The Bab was executed by firing squad in Tabriz on this day in 1850. The very moment the shots were fired, a gale of exceptional severity arose and swept over the whole city. A whirlwind of dust of incredible density obscured the light of the sun and blinded the eyes of the people. The entire city remained enveloped in that darkness from noon till night. Even so strange a phenomenon, following immediately in the wake of that still more astounding failure of Sám Khán's regiment to injure the Báb, was unable to move the hearts of the people of Tabríz, and to induce them to pause and reflect upon the significance of such momentous events. They witnessed the effect which so marvellous an occurrence had produced upon Sám Khán; they beheld the consternation of the farrásh-báshí and saw him make his irrevocable decision; they could even examine that tunic which, despite the discharge of so many bullets, had remained whole and stainless; they could read in the face of the Báb, who had emerged unhurt from that storm, the expression of undisturbed serenity as He resumed His conversation with Siyyid Husayn; and yet none of them troubled himself to enquire as to the significance of these unwonted signs and wonders.

The martyrdom of the Báb took place at noon on Sunday, the twenty-eighth of Sha'bán, in the year 1266 A.H., thirty-one lunar years, seven months, and twenty-seven days from the day of His birth in Shíráz. (Nabil, The Dawn-Breakers pp. 510 - 517 )

20 October Birth of the Báb. The Báb was born Siyyid ‘Ali-Muhammad on October 20, 1819, in Shiraz, Iran.

12 November Birth of Bahá’u’lláh. Bahá’u’lláh was born Mirza Husayn-’Ali on November 12, 1817, in Tihran, Iran. His mother was Khadijih Khanum and his father Mirza Buzurg-i-Vazir.

(Compilations, NSA USA - Developing Distinctive Baha'i Communities)

26 February-1 March Ayyam-i-Ha, the Intercalary Days, reserved for charity, gift-giving and festivities

Ayyam-i-Ha Interculary Days

"Let the days in excess of the months be placed before the month of fasting" (Katab-i-Aqdas). The Badi’ calendar is based on the solar year of 365 days, 5 hours, and 50 odd minutes. The year consists of 19 months of 19 days each (i.e. 361 days), with the addition of four extra days (five in a leap year). The Báb did not specifically define the place for the intercalary days in the new calendar. The Kitáb-i-Aqdas resolves this question by assigning the "excess" days a fixed position in the calendar immediately preceding the month of Ala’, the period of fasting. For further details see the section on the Bahá’í calendar in The Bahá’í World, volume XVIII.(Baha'u'llah, The Kitab-i-Aqdas, p. 178).

2-20 March Fasting month, during which Baha'is over the age of 15 years do not eat or drink from sunrise to sunset.

26 November Day of the Covenant. This day celebrates Baha'u'llah's appointment of His son, Abdu'l-Baha, as the Centre of the Covenant, to whom His followers should turn after His passing. Suspension of work is not obligatory on this holy day.

28 November Ascension of Abdu'l-Baha. This day marks the passing of Abdu'l-Baha, the son of Baha'u'llah, in 1921. Suspension of work is not obligatory on this holy day.

`The Day of the Covenant Nov. 26th and the Day of the Ascension Nov. 28th, anniversaries of the birth and the Ascension of Abdu'l-Baha must be observed by the friends coming together, but work is not prohibited. In other words the friends must regard observance of these two anniversaries as obligatory - but suspension of work not to be regarded as obligatory.'

Briefly, every nation has a day known as a holiday which they celebrate with joy. In the sacred laws of God, in every cycle and dispensation, there are blessed feasts, holidays and workless days. On such days all kinds of occupations, commerce, industry, agriculture etc., are not allowed. Every work is unlawful. All must enjoy a good time, gather together, hold general meetings, become as one assembly, so that the national oneness, unity and harmony may become personified in all eyes. As it is a blessed day it should not be neglected or without results by making it a day limited to the fruits of mere pleasure. During such blessed days institutions should be founded that may be of permanent benefit and value to the people so that in current conversation and in history it may become widely known that such a good work was inaugurated on such a feast day. Therefore, the intelligent must search and investigate reality to find out what important affair, what philanthropic institutions are most needed and what foundations should be laid for the community on that particular day, so that they may be established. For example, if they find that the community needs morality, then they may lay down the foundation of good morals on that day. If the community be in need of spreading sciences and widening the circle of knowledge, on that day they should proceed in that direction, that is to say, direct the thoughts of all the people to that philanthropic cause. If, however, the community is in need of widening the circle of commerce or industry or agriculture they should start the means so that the desired aim may be attained. If the community needs protection, proper support and care of orphans, they should act upon the welfare of the orphans, etc. Such undertakings that are beneficial to the poor, the weak and the helpless should be pursued in order that, on that day, through the unity of all and through great meetings, results may be obtained, the glory and blessings of that day may be declared and manifest.