How does a hardened heart soften, and does it require a long time to achieve reverence when remembering Allah?

The treatment for hardness of heart requires struggle, perseverance, and time. This varies according to the states of hearts and levels of determination. Allah may soften a servant's heart quickly, for He is the turner of hearts. Some means for treating hardness of heart have been mentioned in fatwas numbered 50335 and 43933.