From the Universal House of Justice quoting the Beloved Guardian, Shoghi Effendi:

On page 25[1] of “The Advent of Divine Justice” the beloved Guardian is describing the requirements not only of chastity, but of “a chaste and holy life” — both the adjectives are important. One of the signs of a decadent society, a sign which is very evident in the world today, is an almost frenetic devotion to pleasure and diversion, an insatiable thirst for  54  amusement, a fanatical devotion to games and sport, a reluctance to treat any matter seriously, and a scornful, derisory attitude towards virtue and solid worth. Abandonment of “a frivolous conduct” does not imply that a Bahá’í must be sour-faced or perpetually solemn. Humour, happiness,joy are characteristics of a true Bahá’í life. Frivolity palls and eventually leads to boredom and emptiness, but true happiness and joy and humour that are parts of a balanced life that includes serious thought, compassion and humble servitude to God, are characteristics that enrich life and add to its radiance.

[1 On page 25 in the 1956 U.S. edition; on page 30 in the 1984 U.S. edition.]

Compilations, The Compilation of Compilations vol. I, p. 53

MORNING:

The word of God which the Supreme Pen hath recorded on the eighth leaf of the Most Exalted Paradise is the following: Schools must first train the children in the principles of religion, so that the Promise and the Threat recorded in the Books of God may prevent them from the things forbidden and adorn them with the mantle of the commandments; but this in such a measure that it may not injure the children by resulting in ignorant fanaticism and bigotry.

—His Holiness Bahá’u’lláh

Tablets of Bahá’u’lláh, p. 68

EVENING:

The word of God which the Supreme Pen hath recorded on the fifth leaf of the Most Exalted Paradise is this: Above all else, the greatest gift and the most wondrous blessing hath ever been and will continue to be Wisdom. It is man’s unfailing Protector. It aideth him and strengtheneth him. Wisdom is God’s Emissary and the Revealer of His Name the Omniscient. Through it the loftiness of man’s station is made manifest and evident. It is all-knowing and the foremost Teacher in the school of existence. It is the Guide and is invested with high distinction. Thanks to its educating influence earthly beings have become imbued with a gem-like spirit which outshineth the heavens. In the city of justice it is the unrivalled Speaker Who, in the year nine, illumined the world with the joyful tidings of this Revelation. And it was this peerless Source of wisdom that at the beginning of the foundation of the world ascended the stair of inner meaning and when enthroned upon the pulpit of utterance, through the operation of the divine Will, proclaimed two words. The first heralded the promise of reward, while the second voiced the ominous warning of punishment. The promise gave rise to hope and the warning begat fear. Thus the basis of world order hath been firmly established upon these twin principles. Exalted is the Lord of Wisdom, the Possessor of Great Bounty.

—His Holiness Bahá’u’lláh

Tablets of Bahá’u’lláh, p. 65

FROM THE CENTRE OF THE CAUSE OF GOD ‘ABDU’L-BAHÁ:

It has been shown conclusively therefore that the foundation of the religion of God remains permanent and unchanging. It is that fixed foundation which insures the progress and stability of the body politic and the illumination of humanity. It has ever been the cause of love and justice amongst men. It works for the true fellowship and unification of all mankind for it never changes and is not subject to supersedure. The accidental or non-essential laws which regulate the transactions of the social body and everyday affairs of life are changeable and subject to abrogation.

Let me ask what is the purpose of prophethood? Why has God sent the prophets? It is self-evident that the prophets are the educators of men and the teachers of the human race. They come to bestow universal education upon humanity, to give humanity training, to uplift the human race from the abyss of despair and desolation and enable man to attain the apogee of advancement and glory. The people are in darkness; the prophets bring them into the realm of light. They are in a state of utter imperfection; the prophets imbue them with perfections. The purpose of the prophetic mission is no other than the education and guidance of the people. Therefore we must regard and be on the lookout for the man who is thus qualified; that is to say any soul who proves to be the educator of mankind and the teacher of the human race is undoubtedly the prophet of his age.

Foundations of World Unity, p. 94