Nahj al-Balāgha

وَالرَّابِعُ: أَنْ تَعْمِدَ إِلَى كُلِّ فَرِيضَةٍ عَلَيْكَ ضَيَّعْتَهَا فَتُؤَدِّيَ حَقَّهَا.

the fourth is to fulfil every obligation which you ignored (in the past) so that you may now do justice with it;