…the greatest inter-relation and communication exists between the sons of men without which peace, life and existence is entirely impossible. For a soul independent of all the other soul and without receiving assistance from other sources cannot live for the twinkling of an eye: nay, rather, he will become non-existent and reduced to nothingness: especially among the believers of God between whom material and spiritual communication is developed up to the highest point of perfection. It is this real communication, the essential necessity and requirement of which is the mutual helpfulness, co-operation and confirmation. Without the complete establishment of this divine principle in the hearts of the friends of God, nothing can be accomplished, for they are the hyacinths of one garden, the waves of one sea, the stars of one heaven and the rays of one sun. From every standpoint the essential unity, the luminous unity, the religious unity and the material unity are founded and organized between them.
- ‘Abdu’l-Baha (From a Tablet, Star of the West, vol. 6, no. 17, January 19, 1916)