What is the religious ruling regarding preachers and shaykhs attending seminars and lessons in places where there is much display of adornment (tabarruj) and a lack of adherence to Islamic dress by women?

Delivering lessons and inviting to Allah is a religious obligation, especially in places deprived of prophetic guidance. Every Muslim must invite to Allah with wisdom and good counsel, in compliance with His Almighty saying: "Invite to the way of your Lord with wisdom and good instruction, and argue with them in a way that is best," and His saying: "Say, 'This is my way; I invite to Allah with insight, I and those who follow me.'" Inviting to Allah, enjoining good, and forbidding evil is the duty of every Muslim, and they must cooperate in this great obligation, especially in Western countries, for His Almighty saying: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression."