Surah 7. Al-A'raf, Ayah 202

I.e., by goading them to anger or trying to engage them in futile argument. "Their brethren" are those who wilfully remain ignorant of the truth (with the pronoun referring to the God-conscious). The conjunctive particle wa preceding this clause has here the meaning of "although" or "even though".

 lit., their brothers.

We go back to consider the ungodly, whom we left at verse 198, in order to be taught our behaviour towards evil. The forces of evil never relax their efforts to draw their "brethren" (those who go into their family) deeper and deeper into the mire of sin and destruction.