2:185 The month of Ramadhan has been chosen for this collective training since this is the month in which the Qur’an was revealed - a Guidance for mankind, clearly explaining the ‘why’ of every Rule. And it is the Criterion of right and wrong. Hence, whoever witnesses this month should participate in the program of Abstinence. But if any of you is sick or on a journey, let him practice Abstinence for the same number of days later. Allah desires for you ease, and He desires for you no hardship.
The postponement is for enabling you to complete the period. The objective of this training is to establish the Supremacy of Allah (on earth) for He has shown you a well-lighted road, and for you to express gratitude in practice.
[The Qur’an was revealed upon the Prophet’s heart in Ramadhan of 610 C.E. Thereafter, it was conveyed to people in stages. 2:87-97, 2:185, 9:32-33, 14:1, 16:2, 17:85-86, 26:193, 42:52, 44:1-4, 70:4, 81:17-19, 97:1. The concepts therein are not defunct theories and empty hypotheses. It has a Permanent Universal Code of Values and Laws. The yearly training of Abstinence in this month connects the Message with intensive reflection and study.