Posted every second day…

March 4

Thou hast written about the Fast. This is a most weighty matter and thou shouldst exert thine utmost in its observance. It is a fundamental of the Divine law, and one of the pillars of the religion of God. 
(‘Abdu’l-Baha, compilation ‘The Importance of Obligatory Prayer and Fasting’, compiled by Research Department of the Universal House of Justice; published in The American Baha'i, September 2000)