The first one has already been discussed.
Secondly, the phrase "God in disguise of poor person" was coined by Swami Vivekananda. The meaning of this word was deep rooted in the inner part of his heart.. 'Service to mankind is service to god' was his motto.To analyse his concept of peoples awareness, Jagadish Babu cited three examples from the first part of the 'series of Letters' (Patrabali)-Page left/ written by him in India and abroad.
The quotations from "apamanita' written by Rabindranath also reveals the same idea with that of Vivekananda. ( page -rt).
Thirdly, Swami Vivekananda, the great soul loved and revered in East and West alike as the rejuvenator of Hinduism in India and the preacher of its truth abroad, he wrote poem, (Pic -below)