Shaykh Nuh Ha Mim Keller is a contemporary Shafi'i scholar known for translating Umdat al-Salik (Reliance of the Traveller) and teaching classical jurisprudence and spirituality to English speakers.
His SeekersGuidance lecture on bid'a is a primary English-language gateway to the five-category framework used in this site's bid'a article.
The concept of bid'a in Islamic Sharia
SeekersGuidance
Includes Shaykh Nuh Keller's lecture on innovation.