عَنْ عُرْوَةَ عَنْ عَائِشَةَ قَالَتْ: وَاللَّهِ مَا سَبَّحَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ سُبْحَةَ الضُّحَى قَطُّ وَإِنِّي لَأُسَبِّحُهَا وَقَالَتْ: إِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ كَانَ يَتْرُكُ الْعَمَلَ وَهُوَ يُحِبُّ أَنْ يَعْمَلَهُ خَشْيَةَ أَنْ يَسْتَنَّ بِهِ النَّاسُ فَيُفْرَضَ عَلَيْهِمْ، وَكَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ يُحِبُّ مَا خَفَّ عَلَى النَّاسِ مِنَ الْفَرَائِضِ
It is narrated from Sayyida Aisha (may Allah be pleased with her), she says: By Allah! The Messenger of Allah (peace and blessings be upon him) never performed the Duha (forenoon) voluntary prayers, but I used to perform this prayer. The real matter is that the Messenger of Allah (peace and blessings be upon him), despite liking an action, would sometimes abandon it, because he feared that people would follow him and that action would become obligatory. The Messenger of Allah (peace and blessings be upon him) liked to make things easier for people regarding obligatory matters.