In the beginning was the Word...
John 1:1
We read in Genesis 15 the account of Abram and the son promised him by the LORD. in verse 1 we read,
After these things, the word of the LORD came to Abram in a vision saying, "Do not fear, Abram, I am a shield to you; your reward shall be very great." (Gen 15:1 NASB)
We see that the word of the LORD came to Abram. This was in a vision. Was it a voice from heaven, or did this word come in some other way? Abram responds to this with a request for an heir, a child, as he was childless (Gen 15:2-3). Now the word of the LORD comes to Abram. First in a vision and now as a person as we will see.
Then behold the word of the LORD came to him saying, "This man will not be your heir, but one who will come forth from your own body, he shall be your heir." And He took him outside and said, "Now look toward the heavens, and count the stars, if you are able to count them." And He said to him, "So shall your descendants be." (Gen 15:4-5 NASB)
Notice that the word of the LORD is personified in these two verses. The pronoun He, is used in referring to the word of the LORD here. The word of the LORD takes Abram outside and asks him to count the stars. This is someone present before Abram who then speaks to him further and promises Abram that his descendants would be exceedingly numerous.
Abram believed in the LORD; and He reckoned it to him as righteousness (Gen 15:6)
Abram believes in the LORD in whose presence he is standing. The word of the LORD reveals himself to Abram as the LORD who called him out of Ur to go to a land which he would be given to possess. This divine being then makes a covenant with Abram as well. (Gen 15:7-21). So who is this?
We read in John 1:18, that no one has seen God at anytime, but the only begotten in the bosom of the Father has explained or revealed Him. This is Jesus, the one in whom all the fullness of deity dwells (Col 2:9). This same Jesus is revealed as the Word in John 1:1-5, 14. The one who came to Abram, the one in whom Abram believed was Jesus Himself, appearing in a pre-incarnate form as the word of the LORD.