Ibn Al-Qayyim [رحمه الله] said:

❝When the sun-light of the Sunnah rises in the heart of a slave of Allaah then the smog of all Bida is dispersed from his heart.❞

[Mudarij As-Salikeen, (1/374) | Translated By Abbas Abu Yahya Miraath al-Anbiyya]