1 John 1:1-4 That which was from the beginning, which we have heard, which we have seen with our eyes, which we looked upon and have touched with our hands, concerning the word of life-- 2 the life was made manifest, and we have seen it, and testify to it and proclaim to you the eternal life, which was with the Father and was made manifest to us-- 3 that which we have seen and heard we proclaim also to you, so that you too may have fellowship with us; and indeed our fellowship is with the Father and with his Son Jesus Christ. 4 And we are writing these things so that our joy may be complete.
The Apostle John wrote about the Apostolic witness of Jesus. The Apostle's witnessed Jesus as he spoke to the crowds who gathered before him. They witnessed him heal. They were witnesses of the death and resurrection of their Master. What they witnessed in Jesus confirmed that they were witnessing something beyond his physical presence with them in their time. They were witnessing a timeless wisdom, power and purpose. What Jesus proved on earth was something greater than earthly comprehension. Jesus spoke and healed and conquered death with the power, wisdom and purpose beyond this world.
John testifies of Jesus in the only way that could possibly explain the reality of Jesus. He uses the term, "That Which." John does not say, "Jesus, who was from the beginning." He does not say, "He, who was from the beginning." It seems awkward and confusing for John to say, "That Which was from the beginning." It is an awkward statement that makes complete sense when we read the gospels and see the reality of who Jesus is. He is God. He is the one who is the I AM (John 8:56). He has the power to make the blind see, the lame walk, the deaf hear. He could heal with the power of one who created in the first place. He could command the wind and the waves. He had persuasion over the elements as if the one who created them. He had wisdom beyond human reason to stump his greatest opponents. He could forgive sins. He was born of a virgin and rose from the grave.
When John describes Jesus as "That Which," he is appealing to the reader to know that Jesus is beyond any normal human. He is greater and beyond comprehension. He is the eternal, self-existent God. He is "That Which was from the beginning."
What makes this even more amazing for John is the fact that John rubbed shoulders with this one who is "That Which." John saw him with his eyes and heard him with his ears and touched him with his hands. In fact, at one time John was reclining at a table simply leaning- physically - on Jesus (John 13:23).
When John wrote the first sentences of his first letter, he wanted the readers to know that he had not witnessed any man. He had witnessed God, the Creator, the self-existent One, in the flesh. His witness, and that of the other Apostles, was of the only One in human existence who has authority and power to save. When you believe in the Jesus that the Apostles witnessed, you are believing in "That Which was from the beginning."