It was narrated from Anas that they said: "O Messenger of Allah, why don't you marry a woman from the Ansar?" He said: "They are very jealous."  

عَنْ أَنَسٍ قَالُوا يَا رَسُولَ اللَّهِ أَلاَ تَتَزَوَّجُ مِنْ نِسَاءِ الأَنْصَارِ قَالَ إِنَّ فِيهِمْ لَغَيْرَةً شَدِيدَةً