On Da`wah Topics for Muslims

Answered by Sayyidi al-Ḥabīb `Umar bin Hafīẓ (may Allāh preserve him and benefit us by him).

When speaking to the Muslims what are the topics that have the most effect on their hearts?

Speaking about Allāh and His Messenger (may Allāh bless him and grant him peace) is the greatest way to affect people and Muslims, as is focussing on good character.