December 15

O Spiritual Assembly! [Muskegon, Michigan]

Everything produces an impression in existence and results in the course of ages. The (earthly) assemblies established in the different parts of Europe, Asia and America have no results save the help of the physical and the mortal life in this lesser world, for the removal of its conditions and reformation of its customs, and in the end no name will remain thereof. But every spiritual assembly of solid foundation, good structure and unwavering constancy will last forever and will send forth its illumination unto all regions.

Observe the gatherings of the disciples after Christ: Their light is still shining, their power is still revealing and their trumpets still resounding throughout the ages. Such is the spiritual meeting. 
(‘Abdu’l-Baha, ‘Tablets of ‘Abdu’l-Baha, vol. 1)