Conversation so far:
What were Al-Khalil ibn Ahmad al-Farahidi's views?
Al-Farahidi's eschewing of material wealth has been noted by a number of biographers.
How did Al-Khalil ibn Ahmad al-Farahidi adopt his own views? Was Al-Khalil ibn Ahmad al-Farahidi pious?
Known for his piety and frugality
What other views did Al-Khalil ibn Ahmad al-Farahidi have besides schewing of material wealth?
Al-Farahidi distinguished himself via his philosophical views. He reasoned that a man's intelligence peaked at the age of forty - the age when the Islamic prophet Muhammad began his call

Question: What did Muhammad do at 40?
Self-contained rewrite: What did Islamic prophet Muhammad do at 40?