"He should consume every wayward thought with the flame of His loving mention ..."

"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. He should succour the dispossessed, and never withhold his favour from the destitute. He should show kindness to animals, how much more unto his fellow-man, to him who is endowed with the power of utterance. He should not hesitate to offer up his life for his Beloved, nor allow the censure of the people to turn him away from the Truth. He should not wish for others that which he doth not wish for himself, nor promise that which he doth not fulfil. With all his heart should the seeker avoid fellowship with evil doers, and pray for the remission of their sins. He should forgive the sinful, and never despise his low estate, for none knoweth what his own end shall be. How often hath a sinner, at the hour of death, attained to the essence of faith, and, quaffing the immortal draught, hath taken his flight unto the celestial Concourse. And how often hath a devout believer, at the hour of his soul’s ascension, been so changed as to fall into the nethermost fire. Our purpose in revealing these convincing and weighty utterances is to impress upon the seeker that he should regard all else beside God as transient, and count all things save Him, Who is the Object of all adoration, as utter nothingness."

-Bahá'u'lláh, The Kitáb-i-Íqán (The Book of Certitude), pp. 193-195