‘Abdu’l-Bahá said:

“God’s greatest gift to man is that of intellect, or understanding.”
(Paris Talks by ‘Abdu’l-Bahá, p. 41)

Bahá’u’lláh wrote:

“Know thou that, according to what thy Lord, the Lord of all men, hath decreed in His Book, the favors vouchsafed by Him unto mankind have been, and will ever remain, limitless in their range. First and foremost among these favors, which the Almighty hath conferred upon man, is the gift of understanding. His purpose in conferring such a gift is none other except to enable His creature to know and recognize the one true God – exalted be His glory…”
(Gleanings from the Writings of Bahá’u’lláh, p. 194)

“The beginning of all things is the knowledge of God, and the end of all things is strict observance of whatsoever hath been sent down from the empyrean of the Divine Will that pervadeth all that is in the heavens and all that is on the earth.”
(Gleanings from the Writings of Bahá’u’lláh, p. 5)

“…Knowledge is as wings to man’s life, and a ladder for his ascent.  Its acquisition is incumbent upon everyone.  The knowledge of such sciences, however, should be acquired as can profit the peoples of the earth, and not those which begin with words and end with words…”
(Tablets of Bahá’u’lláh, p. 51-52)

“The source of all learning is the knowledge of God, exalted be His Glory, and this cannot be attained save through the knowledge of His Divine Manifestation.”
(Tablets of Bahá’u’lláh, p. 156)