1:2 beginning. The definite article has been supplied. The actual Greek is en arche—that is, “in beginning.” The “Word of God” thus was there before the creation of the space-mass-time universe, so that John’s “beginning” even antecedes the Genesis “beginning,” extending without an initial beginning into eternity past, before even time was created. Note also John 17:24, where Jesus, in His humanity, acknowledged that He was with the Father, and loved by the Father, “before the foundation of the world.”
1:2 with God. The “Word of God” (i.e., Jesus Christ) was God, yet also “with God.” Thus God is both personal and plural (in a uni-plural sense only, however, a mysterious category that makes sense only in terms of the doctrine of the Trinity).