The passage above is from the first passage in “Selections from the Writings of ‘Abdu’l-Baha”, a collection of ‘Abdu’l-Baha’s letters to Baha’is and other interested people. It is a well-spring of truth and reflects the incredible way in which ‘Abdu’l-Baha’ lived the message of Baha’u’llah and explained it to humanity. The entire book may be found here. The passage ends with the following quote-

Soon will your swiftly passing days be over, and the fame and riches, the comforts, the joys provided by this rubbish-heap, the world, will be gone without a trace. Summon ye, then, the people to God, and invite humanity to follow the example of the Company on high. Be ye loving fathers to the orphan, and a refuge to the helpless, and a treasury for the poor, and a cure for the ailing. Be ye the helpers of every victim of oppression, the patrons of the disadvantaged. Think ye at all times of rendering some service to every member of the human race. Pay ye no heed to aversion and rejection, to disdain, hostility, injustice: act ye in the opposite way. Be ye sincerely kind, not in appearance only. Let each one of God’s loved ones center his attention on this: to be the Lord’s mercy to man; to be the Lord’s grace. Let him do some good to every person whose path he crosseth, and be of some benefit to him. Let him improve the character of each and all, and reorient the minds of men. In this way, the light of divine guidance will shine forth, and the blessings of God will cradle all mankind: for love is light, no matter in what abode it dwelleth; and hate is darkness, no matter where it may make its nest. O friends of God! That the hidden Mystery may stand revealed, and the secret essence of all things may be disclosed, strive ye to banish that darkness for ever and ever.