For the word of God is living and active, sharper than any two-edged sword, piercing to the division of soul and of spirit, of joints and of marrow, and a discerning the thoughts and intentions of the heart (Hebrews 4:12).
The human race is advancing in knowledge and technology. Today, in medical sciences, there are various diagnostic equipments which can detect ailments hidden in the body.
However, these medical advancements and equipments have limits. You can’t use an MRI or CT scan for example to detect the disease of the soul— sin. Only God’s word can.
The human race is plagued with sin. We are spiritually dead. We are sick with sin from head to toe and the word of God diagnoses this with precision. The word is a mirror, showing to us our true self. It lays bare the evil dispositions of our hearts. Just as medical diagnosis aids in finding treatment for our ailment, God through His word provides us with the treatment for our ailing souls.
The word is living; it has life. It points us to Christ through faith for the salvation of our souls unto eternal life. The word convicts, it reproofs, corrects, and trains us in righteousness. God through His word renews and transform us. He washes and sanctifies us by His word.
God is gracious. He has not left us in our desperate state without a remedy. He has given us His word to bring us into communion with Himself. The word is living. It has life.
The words that I have spoken to you are spirit and life (John 6:63).
Further Studies: Psalm 23:3, 139:1-16, Jeremiah 17:9, 23:29, John 17:17 Romans 3:23, 12:1-2, 2Timothy 3:16