According to Hebrews 4:12, “the word of God is alive and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart.” The “word of God” here is the written or spoken Word, not the Logos of John 1.
The description of the Bible as “living” means that it has a vital power inherent to itself. The written Word of God accomplishes God’s purposes (Isaiah 55:11); the preaching of the Holy Scriptures brings about God’s desired effects. The Bible is unlike other books, whatever emotional or social effects they may produce, in that it brings about lasting, supernatural change within a person. “Faith comes from hearing the message, and the message is heard through the word about Christ” (Romans 10:17).
Jesus likened the Word of God to seed in His parable of the sower (Matthew 13:1–23). Seed, like the Bible, is not dead, but living, and it has the ability to bring forth more life abundantly. Seeds produce a crop (verse 23).
The Bible, as the living Word of God, is not inert or powerless, as seen in the actions attributed to the Word in the rest of Hebrews 4:12: the Bible “penetrates” deep within us and “judges” our hearts and motivations. It is “active,” not passive. The Bible is resisted or ignored to our own peril (Hebrews 2:1–3).
We see the living Word of God in action in the pages of the Bible. On the Day of Pentecost, Peter preached the Word of God, and his audience “were cut to the heart and said to Peter and the other apostles, ‘Brothers, what shall we do?’” (Acts 2:37). Three thousand people were saved that day (verse 41). Later, as the apostles continued to preach, the number in the church grew to five thousand, because “many of those who had heard the word believed” (Acts 4:4, ESV). God’s Word, living and active, does not return to Him void.
The Bible is the living Word of God because it is the message given to us from the “living God” (Hebrews 3:12). The God who is alive works in this world through His living Word in conjunction with the Holy Spirit (see Ephesians 6:17). Jesus spoke of the life-giving property of His words: “The words I have spoken to you—they are full of the Spirit and life” (John 6:63). The word of our Lord is efficacious for our salvation and sanctification (Acts 13:48; John 17:17).