"For 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." -Hebrews 4:12
The Word of God can take on several different forms. There is often confusion associated with this term. To avoid this confusion, let's first examine the phrasing by rightly identifying the Word of God through its various forms.
"In the beginning was the Word, and the Word was with God, and the Word was God." -John 1:1
John refers to the Word of God as Jesus Christ and we know this because of verse 14, where he writes that "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." A couple of implications are realized from these verses.
First, when God created the universe in Genesis 1, Christ was there and the reason for it all. John 1:2-4 says that Christ
"...was in the beginning with God. All things were made through him, and without him was not any thing made that was made. In him was life, and the life was the light of men."
Thus, we can appreciate Genesis 1:3 through a different lens when we read that God spoke Light into existence because Christ is that Light. It might seem paradoxical; "How can Christ create Himself?" But, this Light was in fact the Word of God as a Person.
Perhaps a better understanding of Christ as 'the Word' can be found in the first chapter of Hebrews where verse two reads that God has spoken to us through His Son, Jesus Christ, and that the universe was made through Him.
The Word of God can take the form of commandments, or decrees. For instance, in Genesis 1:3, God said, "Let there be light", and there was light. Genesis chapter one has many examples of God's decrees that always brought about significant change. God's decrees will always produce something of sustenance, or merit, and bring about what He intended. Isaiah 55:11 says,
"So shall my word [God] be that goes out from my mouth; it shall not return to me empty, but it shall accomplish that which I purpose and shall succeed in the thing for which I sent it."
God's Word Through Personal Address
Throughout Scripture, God's Word often takes the form of a personal address. The earliest account of God speaking directly to a person was in the Garden of Eden in Genesis 2:16-17,
"And the Lord God commanded the man, saying, “You may surely eat of every tree of the garden, but of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die.”
There is a multitude of other verses throughout Scripture that involve God speaking directly to an individual or group of people like the Israelites (Genesis 4:10-12; Exodus 20:1; Matthew 3:17)