"He should consume every wayward thought with the flame of His loving mention, and, with the swiftness of lightning, pass by all else save Him."

"That seeker must at all times put his trust in God, must renounce the peoples of the earth, detach himself from the world of dust, and cleave unto Him Who is the Lord of Lords. He must never seek to exalt himself above any one, must wash away from the tablet of his heart every trace of pride and vainglory, must cling unto patience and resignation, observe silence, and refrain from idle talk. For the tongue is a smouldering fire, and excess of speech a deadly poison. Material fire consumeth the body, whereas the fire of the tongue devoureth both heart and soul. The force of the former lasteth but for a time, whilst the effects of the latter endure a century.

That seeker should also regard backbiting as grievous error, and keep himself aloof from its dominion, inasmuch as backbiting quencheth the light of the heart, and extinguisheth the life of the soul. He should be content with little, and be freed from all inordinate desire. He should treasure the companionship of those that have renounced the world, and regard avoidance of boastful and worldly people a precious benefit. At the dawn of every day he should commune with God, and with all his soul persevere in the quest of his Beloved. He should consume every wayward thought with the flame of His loving mention, and, with the swiftness of lightning, pass by all else save Him."

-Bahá'u'lláh, The Kitáb-i-Íqán, pp. 193-194