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 discerning the thoughts and intentions of the heart. (Hebrews 4:12, ESV)
The "Word of God" has several different meanings throughout the Bible. The word "word" is translated from the Greek word (the language the New Testament was originally written in) logos. The word itself has many possible meanings, which is why the phrase can carry multiple meanings. The Word of God could mean the speech of God or maybe God's decrees (Genesis 1:3, for example). It could be the actual words spoken to a person or people, like when God spoke to Moses (Exodus 20:1-3) or when God spoke to the crowd at Jesus' baptism (Matthew 3:17). There are many Old Testament instances of God speaking through a human prophet; Deuteronomy 18:18-20 explains how God spoke through these men. And of course the Word of God can mean the written scriptures, that is, the Bible. (Please see Joshua 24:26 or 1 Corinthians 14:37.) And there are rare Scriptures that indicate that the Word of God is also Jesus Christ.
(1) In the beginning was the Word, and the Word was with God, and the Word was God. (2) He was in the beginning with God. (3) All things were made through him, and without him was not any thing made that was made. (John 1:1-3, ESV)Here we clearly see that the Word was with God but was also God. The reference to "the beginning" is a reference to Genesis 1:1 when God was creating the world. This is not simply spoken words or the Scriptures. And we see that all of creation was made through the Word. But what or who is this Word. John 1:14 gives us the answer:
And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth. (John 1:14, ESV)Clearly this Word is not like the aloof clockmaker; this God entered flesh and walked among the creation.
Getting back to Hebrews 4:12, it is most likely that the Word of God is the Scriptures (although it is beautiful to see the deeper connection between the Scriptures and the Christ). Often the Holy Spirit uses what is written to convict us, to show us where we have blemishes in our intentions and attitudes. And through this conviction we find we can turn to Jesus Christ, who has made a way for us to escape the punishment of sin and dwell with God eternally. If, however, God is like the clockmaker, why do our thoughts and attitudes need investigation? Why even leave man with the living and active Word of God at all? No, this God is not like the clockmaker. This God is living and active in the lives of his creation.