[Legal responsibility of human action and God’s sustenance and guidance]
وَالاسْتِطَاعَةُ مَعَ الْفِعْلِ، وَهِيَ حَقِيقَةُ الْقُدْرَةِ الَّتِي يَكُونُ بِهَا الْفِعْلُ، وَيَقَعُ هذَا الاسْمُ عَلَى سَلاَمَةِ الأَسْبَابِ وَالآلاتِ وَالْجَوَارِحِ، وَصِحَّةُ التَّكْلِيفِ تَعْتَمِدُ هذِهِ الاسْتِطَاعَةَ. وَلاَ يُكَلَّفُ الْعَبْدُ بِمَا لَيْسَ فِي وِسْعِهِ.
021- Ability (istṭāʿa) accompanies the actions, and it is the real essence of power that produces the action; and this term applies to the soundness of causes, instruments, and limbs. And the validity of imposing a legal responsibility (taklīf) assumes ability. A person is not legally responsible [to do] what is not in his capacity.1