In short, they did show their reverence for the Ibrahimi faith at least by doing it during four months of the year when they would abstain from fighting and killing. But, they did not observe the order of the months in a year according to which four of them were fixed as the sacred months. This was what they juggled with seeking interpretations to suit their needs or fancies.
In the first verse (36), it is said:
إِنَّ عِدَّةَ ٱلشُّهُورِ عِندَ ٱللَّهِ ٱثْنَا عَشَرَ شَهْرًا
Surely, the number of months with Allah is twelve
Here, the word: عِدَّةَ {‘iddah) appears in the sense of number and شهُورِ (shuhur) is the plural of شهرِ (shahr) which means month. The sense of the verse is that the number of months, in the sight of Allah, is set as twelve. No one has the right to decrease or increase it.
Then, by placing the phrase: فِى كِتَـٰبِ ٱللَّهِ (fi kitabillah: as written in the Book of Allah), it was stressed that this numerical setting of the months stood recorded in the Preserved Tablet (al-lawh al-mahfuz) since eternity. Then, by saying: يَوْمَ خَلَقَ ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضَ (on the day He created the heavens and the Earth), it was indicated that the Divine decree was, though, promulgated in eternity, but this order and setting of the months came into being when the heavens and the Earth were created.
After that, it was said: مِنْهَآ أَرْبَعَةٌ حُرُمٌ (of which there are Four Sacred Months). It means that, out of these twelve months, four are sacred. They have been called حرمٌ hurum (sanctified ones) in the sense that fighting and killing is prohibited during these month, and also in the sense that these months are blessed and it is obligatory to hold them in due esteem and that acts of worship during these become more reward worthy. The first injunction out of the two was abrogated in the Shari’ah of Islam. But, the second one, that of increased reverence, esteem and devotion to Ibadah during this period still remains operative in Islam.
In his address of the Day of Sacrifice during the Last Hajj, the Holy Prophet (SAW) explained these months by saying: ‘Three months are consecutive – Dhu al-Qa’dah, Dhu al-Hijjah, Muharram – and one month is that of Rajab.’ But, there were two sayings of the Arabs regarding the month of Rajab. Some tribes used to call the month we know as Ramadan the month of Rajab while, as seen by the tribe of Mudar, Rajab was the month which comes in between Jumada ath-Thaniah and Sha’ban. Therefore, the Holy Prophet (SAW) – by mentioning this month as ‘Rajab Mudar’ – also made it clear that it means the month of Rajab which is in between Jumada ath-Thaniah and Sha’ban.
Thereafter appears the statement: ذَٰلِكَ ٱلدِّينُ ٱلْقَيِّمُ (That is the right faith). It means that keeping the setting and serial order of months, specially the injunctions pertaining to the Four Sacred Months, according to the very original decree of Allah Almighty is the right faith to hold. Making any changes, alterations, additions or deletions there- in is a sign of crookedness in comprehension and temperament.
[Maarif ul Quran Vol-4 (pg 373-376) , Maktabah Dar al Uloom, Translation by Prof. Muhammad Hasan Askari & Prof. Muhammad Shamim]