Physical fasting is a symbol of abstinence from lust – it is a reminder

Fasting is a symbol. Fasting signifies abstinence from lust. Physical fasting is a symbol of that abstinence, and is a reminder; that is, just as a person abstains from physical appetites, he is to abstain from self-appetites and self-desires. But mere abstention from food has no effect on the spirit. It is only a symbol, a reminder. Otherwise it is of no importance. Fasting for this purpose does not mean entire abstinence from food. The golden rule as to food is, do not take too much or too little. Moderation is necessary. There is a sect in India who practice extreme abstinence, and gradually reduce their food until they exist on almost nothing. But their intelligence suffers. A man is not fit to do service for God with brain or body if he is weakened by lack of food. He cannot see clearly. 

(Words of ‘Abdu’l-Baha, quoted by Miss E. S. Stevens in Fortnightly Review, June 1911; included in ‘Baha'u'llah and the New Era', by Dr. J.E. Esslemont; Star of the West, vol. 3, no. 6, June 24, 1917)  

How will mankind eventually adopt the Cause of Baha’u’llah

One of the Apostles of Baha’u’llah was Mirza ‘Ali-Muhammad, entitled Varqa. Once he asked Bahá'u'lláh, 'How will the Cause of God be universally adopted by mankind?' Bahá'u'lláh said that first, the nations of the world would arm themselves with infernal engines of war, and when fully armed would attack each other like bloodthirsty beasts. As a result, there would be enormous bloodshed throughout the world. Then the wise from all nations would gather together to investigate the cause of such bloodshed. They would come to the conclusion that prejudices were the cause, a major form being religious prejudice. They would therefore try to eliminate religion so as to eliminate prejudice. Later they would realize that man cannot live without religion. Then they would study the teachings of all religions to see which of the religions conformed to the prevailing conditions of the time. It is then that the Cause of God would become universal.

(Adapted from ‘The Revelation of Baha’u’llah, vol. 4’, by Adib Taherzadeh)