The Quran

الأَعرابُ أَشَدُّ كُفرًا وَنِفاقًا وَأَجدَرُ أَلّا يَعلَموا حُدودَ ما أَنزَلَ اللَّهُ عَلىٰ رَسولِهِ ۗ وَاللَّهُ عَليمٌ حَكيمٌ

Muhammad Asad

[The hypocrites among] the bedouin¹ are more tenacious in [their] refusal to acknowledge the truth and in [their] hypocrisy [than are settled people], and more liable to ignore the ordinances which God has bestowed from on high upon His Apostle - but God is all-knowing, wise.²

The words interpolated by me between brackets at the beginning of this sentence are based on the interpretation given by Razi (see also Manar XI, 8), obviously in view of verse 99, which speaks of believers among the bedouin.
Owing to their nomadic way of life and its inherent hardship and crudity, the bedouin find it more difficult than do settled people to be guided by ethical imperatives unconnected with their immediate tribal interests - a difficulty which is still further enhanced by their physical distance from the centres of higher culture and, consequently, their comparative ignorance of most religious demands. It was for this reason that the Prophet often stressed the superiority of a settled mode of life to a nomadic one: cf. his saying, "He who dwells in the desert (al-badiyah) becomes rough in disposition", recorded by Tirmidhi, Abu Da'ud, Nasa'i and Ibn Hanbal on the authority of Ibn 'Abbas, and a similar Tradition, on the authority of Abu Hurayrah, by Abu Da'ud and Bayhaqi.