Surah 2. Al-Baqara, Ayah 189

The reference, at this stage, to lunar months arises from the fact that the observance of several of the religious obligations instituted by Islam - like the fast of Ramadan, or the pilgrimage to Mecca (which is dealt with in verses {196-203}) - is based on the lunar calendar, in which the months rotate through the seasons of the solar year. This fixation on the lunar calendar results in a continuous variation of the seasonal circumstances in which those religious observances are performed (e.g., the length of the fasting-period between dawn and sunset, heat or cold at the time of the fast or the pilgrimage), and thus in a corresponding, periodical increase or decrease of the hardship involved. In addition to this, reckoning by lunar months has a bearing on the tide and ebb of the oceans, as well as on human physiology (e.g., a woman's monthly courses - a subject dealt with later on in this surah).

I.e., true piety does not consist in approaching questions of faith through a "back door", as it were - that is, through mere observance of the forms and periods set for the performance of various religious duties (cf. 2:177 ). However important these forms and time-limits may be in themselves, they do not fulfil their real purpose unless every act is approached through its spiritual "front door", that is, through God-consciousness. Since, metonymically, the word bab ("door") signifies "a means of access to, or of attainment of, a thing" (see Lane I, 272), the metaphor of "entering a house through its door" is often used in classical Arabic to denote a proper approach to a problem (Razi).

 Before Islam, there was a superstitious practice for pilgrims to enter their homes through the back door upon returning from the pilgrimage. The verse suggests that being devoted to Allah wholeheartedly is more important than blindly following old traditions.

There were many superstitions connected with the New Moon, as there are to the present day. We are told to disregard such superstitions. As a measure of time, where the lunar calendar is used, the New Moon is one great sign, for which people watch with eagerness. Muslim festivals, including the Pilgrimage, are fixed by the appearance of the New Moon. The Arabs, among other superstitions, had one which made them enter their houses by the back door during or after the Pilgrimage. This is disapproved, for there is no virtue in any such artificial restrictions. All virtue proceeds from the love and fear of God.

This is a Muslim proverb now, and much might be written about its manifold meanings. A few may be notes here. (1) If you enter a society, respect its manners and customs. (2) If you want to achieve an object honourably, go about it openly and not "by a backdoor". (3) Do not beat about the bush. (4) If you wish success in an undertaking, provide all the necessary instruments for it.