Leniency for the One who Errs, the One who Forgets, and the One who is Forced

On the authority of Ibn Abbas (ra), that the Messenger of Allah (saw) said:

Verily Allah has pardoned [or been lenient with] for me my ummah: their mistakes, their forgetfulness, and that which they have been forced to do under duress.

[hasan hadeeth related by Ibn Majah, and al-Bayhaqee and others]