Almighty Allaah said: “Invite to the way of your Lord with wisdom and fair preaching, and discuss with them using that which is better.” Soorah an-Nahl (16):125. Hikmah here refers to the Qur’aan. That is, Muslims are instructed to use Qur’aanic arguments and proofs when discussing with disbelievers. During discussion, Muslims should not sink to the level of their opponents who may curse and use foul language or gestures. Sahl ibn Sa‘d related that Prophet Muhammad (PBUH) said: “By Allaah, it is better for you that Allaah guide one person [to Islaam] through your efforts than [to have] the most valuable possessions.” Collected by al-Bukhaaree (Sahih al-Bukhari, vol. 4, pp. 122-3, no. 192).