Has God spoken to us about conscience, and what is it that prevents us from committing sins?

The concept of conscience—as it is known today as an absolute source for guiding moral action—has no origin in the Islamic heritage. It emerged in Europe to secularize ethical thought and remove it from the authority of religion.

Conscience alone is not sufficient to enjoin good and forbid evil. Rather, the true foundation that prevents sins and guides to righteousness is faith in God and His absolute sustenance and comprehensive oversight. This faith is what guides the servant to the details of good and evil and strengthens his will.

Human guidance is perfected by the purity of the innate nature (fitra) upon which God created man, inclining to monotheism, alongside the revealed law. "For the soul only attains its perfection, happiness, and salvation through the fitra complemented by the revealed law." Similarly, "God's admonisher in the heart of every Muslim" refers to God's proofs, insights, and knowledge that restrain him from prohibitions.