Abu ‘Uthmaan (rahimahullah) narrates that Hazrat Sa’d (radhiyallahu ‘anhu) said:

The following verse of the Qur’aan Majeed was revealed in my regard:

وَ وَصَّیۡنَا الۡاِنۡسَانَ بِوَالِدَیۡہِ حُسۡنًا ؕ وَ اِنۡ جَاہَدٰکَ لِتُشۡرِکَ بِیۡ مَا لَیۡسَ لَکَ بِہٖ عِلۡمٌ فَلَا تُطِعۡہُمَا ؕ

We have enjoined upon man kindness to parents. And if they (your disbelieving parents) force you to join partners with Me (in My worship) that of which you do not have knowledge, then do not obey them.

I was very obedient to my mother. When I accepted Islam, she said, “O Sa’d! What is this religion that you have innovated? You will either leave this religion, or I will neither speak to you, nor eat nor drink until I die. You will then bear the blame of my death as people will call you ‘the one who killed his mother’.” I replied, “O my mother! Do not do this! I will not leave this religion of mine for anything!”

My mother then remained for one day and night (and according to some narrations, three days and nights) without eating or drinking until she became extremely weak. When I saw her in this condition, I said to her, “O my mother! By Allah! Know that if you had a hundred lives and you lost them all, one by one, I would not leave my religion. If you wish, then eat. Otherwise, do not eat.” When the mother of Hazrat Sa’d (radhiyallahu ‘anhu) saw his determination and devotion to Islam, she realized that he would never renounce Islam and she thus began to eat.

(Siyar A’laam min Nubalaa vol.3 pg. 69, Saheeh Muslim #1748)