The Word of God discerns the thoughts and intentions of the heart

Scripture reference

Hebrews 4:12 (ASV 1901)

12For the word of God is living, and active, and sharper than any two-edged sword, and piercing even to the dividing of soul and spirit, of both joints and marrow, and quick to discern the thoughts and intents of the heart.

Stories

John Townsend was studying to become a clergyman when the Word of God powerfully convicted him of his own unsaved state. John abandoned his vocational ambition and sought to first know the Saviour for himself.
Two Christians dared the odds and pushed their way through to the prime minister of Romania, Gheorghiu Dej, to whom they boldly declared the word of God. Though they were imprisoned for their daring witness, their words had sown seeds that would later bear fruit in the heart of Gheorghiu Dej.