From the Writings of ‘Abdu’l-Bahá
O musician of God! ... The songsters of fellowship that abide in the gardens of holiness must pour forth such a triumphant burst of songs in this age that the birds in the fields may wing their flight in a transport of delight; and in this divine festival, this heavenly banquet, they should play the lute and the harp, and the viol and the lyre in such wise that the people of east and west may be filled with exceeding joy and gladness, and be carried away with exultation and happiness. Now it behoveth thee to raise the melody of that heavenly lyre and to perform music on that celestial lute, thus causing Bárbud1 to return to life and Rúdakí2 to be solaced and Fárábí3 to become restless and Ibn-i-Síná4 to be guided to the Sinai of God. Upon thee be salutation and praise.
I earnestly hope that thou wilt memorize all the Persian poems revealed by the Blessed Beauty and wilt sing them in a voice of incomparable sweetness at Bahá’í meetings and gatherings. The day is not far distant when these poems will be set to Western music and the sweet accents of these songs will reach the Abhá Kingdom with exceeding joy and gladness.
The art of music must be brought to the highest stage of development, for this is one of the most wonderful arts and in this glorious age of the Lord of Unity it is highly essential to gain its mastery. However, one must endeavour to attain the degree of artistic perfection and not be like those who leave matters unfinished.
O nightingale of the rose-garden of God! Singing melodies will bring animation and happiness to the world of humanity, the hearers will be delighted and joyful and their deeper emotions stirred. But this gladness, this sense of emotion is transitory and will be forgotten within a short time. However, praise be to God, thou hast blended thy tunes with the melodies of the Kingdom, wilt impart solace to the world of the spirit and wilt everlastingly stimulate spiritual feelings. This will last forever and endure the revolution of ages and centuries.
O servant of Bahá! Music is regarded as a praiseworthy science at the Threshold of the Almighty, so that thou mayest chant verses at large gatherings and congregations in a most wondrous melody and raise such hymns of praise at the Mashriqu’l-Adhkár to enrapture the Concourse on High. By virtue of this, consider how much the art of music is admired and praised. Try, if thou canst, to use spiritual melodies, songs and tunes, and to bring the earthly music into harmony with the celestial melody. Then thou wilt notice what a great influence music hath and what heavenly joy and life it conferreth. Strike up such a melody and tune as to cause the nightingales of divine mysteries to be filled with joy and ecstasy.
I rejoice to hear that thou takest pains with thine art, for in this wonderful new age, art is worship. The more thou strivest to perfect it, the closer wilt thou come to God. What bestowal could be greater than this, that one’s art should be even as the act of worshipping the Lord? That is to say, when thy fingers grasp the paintbrush, it is as if thou wert at prayer in the Temple.
Among the greatest of all great services is the education of children, and promotion of the various sciences, crafts and arts. Praised be God, ye are now exerting strenuous efforts toward this end. The more ye persevere in this most important task, the more will ye witness the confirmations of God, to such a degree that ye yourselves will be astonished.
O bird that singeth sweetly of the Abhá Beauty! In this new and wondrous dispensation the veils of superstition have been torn asunder and the prejudices of eastern peoples stand condemned. Among certain nations of the East, music was considered reprehensible, but in this new age the Manifest Light hath, in His holy Tablets, specifically proclaimed that music, sung or played, is spiritual food for soul and heart.
The musician’s art is among those arts worthy of the highest praise, and it moveth the hearts of all who grieve. Wherefore, O thou Shahnáz,5 play and sing out the holy words of God with wondrous tones in the gatherings of the friends, that the listener may be freed from chains of care and sorrow, and his soul may leap for joy and humble itself in prayer to the realm of Glory.
(Published in “Selections from the Writings of ‘Abdu’l-Bahá” (Wilmette: Bahá’í Publishing Trust, 1997), paragraphs 74.1–74.2) 
Wherefore, O loved ones of God! Make ye a mighty effort till you yourselves betoken this advancement and all these confirmations, and become focal centres of God’s blessings, daysprings of the light of His unity, promoters of the gifts and graces of civilized life. Be ye in that land vanguards of the perfections of humankind; carry forward the various branches of knowledge, be active and progressive in the field of inventions and the arts. Endeavour to rectify the conduct of men, and seek to excel the whole world in moral character. While the children are yet in their infancy feed them from the breast of heavenly grace, foster them in the cradle of all excellence, rear them in the embrace of bounty. Give them the advantage of every useful kind of knowledge. Let them share in every new and rare and wondrous craft and art.
(“Selections from the Writings of ‘Abdu’l-Bahá”, paragraph 102.3) 
O ye recipients of the favours of God! In this new and wondrous Age, the unshakeable foundation is the teaching of sciences and arts. According to explicit Holy Texts, every child must be taught crafts and arts, to the degree that is needful. Wherefore, in every city and village, schools must be established and every child in that city or village is to engage in study to the necessary degree.
(“Selections from the Writings of ‘Abdu’l-Bahá”, paragraph 109.1) 
O thou son of the Kingdom! All things are beneficial if joined with the love of God; and without His love all things are harmful, and act as a veil between man and the Lord of the Kingdom. When His love is there, every bitterness turneth sweet, and every bounty rendereth a wholesome pleasure. For example, a melody, sweet to the ear, bringeth the very spirit of life to a heart in love with God, yet staineth with lust a soul engrossed in sensual desires.
(“Selections from the Writings of ‘Abdu’l-Bahá”, paragraph 154.3) 
O thou bird of pleasing tones! Thy little book of poems, which were very sweet, was read. It was a source of joy, for it was a spiritual anthem and a melody of the love of God.
Continue as long as thou canst this melody in the gatherings of the beloved; thus may the minds find rest and joy and become in tune with the love of God. When eloquence of expression, beauty of sense and sweetness of composition unite with new melodies the effect is ever great, especially if it be the anthem of the verses of oneness and the songs of praise to the Lord of Glory.
Endeavour your utmost to compose beautiful poems to be chanted with heavenly music; thus may their beauty affect the minds and impress the hearts of those who listen.
(Published in “Tablets of Abdul-Baha Abbas”, (New York: Bahá’í Publishing Committee, 1930 printing), vol. I, p. 59) 
O thou honourable one! Thank thou God that thou art instructed in music and melody, singing with pleasant voice the glorification and praise of the Eternal, the Living. I pray to God that thou mayest employ this talent in prayer and supplication, in order that the souls may become quickened, the hearts may become attracted and all may become inflamed with the fire of the love of God!
The first condition of perception in the world of nature is the perception of the rational soul. In this perception and in this power all men are sharers, whether they be neglectful or vigilant, believers or deniers.
This human rational soul is God’s creation; it encompasses and excels other creatures; as it is more noble and distinguished, it encompasses things. The power of the rational soul can discover the realities of things, comprehend the peculiarities of beings, and penetrate the mysteries of existence. All sciences, knowledge, arts, wonders, institutions, discoveries and enterprises come from the exercised intelligence of the rational soul.
(Published in “Some Answered Questions” (Wilmette: Bahá’í Publishing Trust, 1984), chapter 58, p. 217)