(20) “This is enlightenment for mankind, and guidance and mercy for people who have certainty.”

That is, “This”—the Noble Quran and the Wise Reminder—“is enlightenment for mankind”: through it, people gain clear insight into all matters, and believers thereby attain benefit, guidance, and mercy.

“For people who have certainty”: through it, they are guided to the straight path in both the foundations and the branches of religion, and through it they attain goodness, joy, and happiness in this world and the Hereafter—which is mercy. Their souls are purified by it, their minds grow, their faith and certainty increase, and the proof is established against those who persist in obstinate rejection.