Quran 2:138 — The Heifer (Al-Baqarah)

Such is GOD's system, and whose system is better than GOD's? "Him alone we worship."

[2:137] If they believe as you do, then they are guided. But if they turn away, then they are in opposition. GOD will spare you their opposition; He is the Hearer, the Omniscient.

[2:139] Say, "Do you argue with us about GOD, when He is our Lord and your Lord? We are responsible for our deeds, and you are responsible for your deeds. To Him alone we are devoted."