Following the examples of Muhammad and the past prophets
Nahj al-Balāgha|Volume 1|Book 1|Chapter 160
[رسول الله (صلى الله عليه وآله وسلم) :] وَلَقَدْ كَانَ فِي رَسُولِ اللهِ(صلى الله عليه وآله) كَاف لَكَ فِي الاْسْوَةِ، وَدَلِيلٌ لَكَ عَلَى ذَمِّ الدُّنْيَا وَعَيْبِهَا، وَكَثْرَةِ مَخَازِيهَا وَمَسَاوِيهَا، إِذْ قُبِضَتْ عَنْهُ أَطْرَافُهَا، وَوُطِّئَتْ لِغَيْرِهِ أَكْنَافُهَا، وَفُطِمَ مِنْ رَضَاعِهَا، وَزُوِيَ عَنْ زَخَارِفِهَا.
[The example of the Holy Prophet :] Certainly, in the Prophet of Allāh — peace and blessing of Allāh be upon him and his progeny — was sufficient example for you and a proof concerning the vices of the world, its defects, the multitude of its disgraces and its evils, because its sides had been constringed for him, while its flanks had been spread for others; he was deprived of its milk and turned away from its adornments.