And take the helmet of salvation, and the sword of the Spirit, which is the word of God: (Eph. 6:17)
According to the original Greek, which refers to Spirit. Thus here we are told that the Spirit is the word of God.
In the beginning was the Word, and the Word was with God, and the Word was God.... And the Word became flesh, and dwelt among us ... (John 1:1, 14).
... Christ: for in him dwelleth all the fullness of the Godhead bodily, (Col. 2:8‑9).
Here we are told that the Word was God and the Word became flesh. So the Spirit is the Word, God is the Word, and this Word, which is God and the Spirit, became flesh, Christ. Do you still think that you can mentally comprehend God?
If ye had known me, ye would have known my Father also: from henceforth ye know him, and have seen him.... Jesus saith unto him, “Have I been so long time with you, and dost thou not know me, Philip? He that hath seen me hath seen the Father; how say eat thou, Show us the Father? Believest thou not that I am in the Father, and the father in me? ... (John 14:7, 9‑10).
Jesus said unto them, Verily, verily, I say unto you, Before Abraham was born, I am. (John 8:68)
I (Jesus) said unto them, Verily, verily, I say unto you, Before Abraham was born, I am. (John 10:30)
Jesus Christ is God, manifested in the flesh.
For I know that this shall turn out to my salvation, through your supplication and the supply of the Spirit of Jesus Christ. (Phil. 1:19)
And because ye are sons, God sent forth the Spirit of his Son into our hearts, saying, Abba, Father. (Gal. 4:6)
Know ye not that ye are a temple of God, and that the Spirit of God dwelleth in you? (1 Cor. 3:16)
Or know ye not that your body is a temple of the Holy Spirit which is in you, which ye have from God? (1 Cor. 6:19)
Believers have the Holy Spirit in them, the Spirit of God in them, and the Spirit of Christ the Son in them. Are these three separate Spirits?
But Peter said, Ananias, why hath Satan filled thy heart to lie to the Holy Spirit ... But Peter said unto her, How is it that you have agreed together to try the Spirit of the Lord? ... (Acts 5:3, 9).
Here we see, by comparing these two verses, that the Holy Spirit is the Spirit of the Lord.
… These things saith he that hath the seven Spirits of God, ... (Rev. 3:1)
... and from the seven Spirits that are before his throne; (Rev. 1:4).
which are the seven Spirits of God, sent forth into all the Earth. (Rev. 5:6)
Just a short interruption here in order to prevent a possible misunderstanding: The number seven in the scriptures signifies completion and/or intensification, in this age. Seven Spirits in these verses does not mean literally seven different Spirits; rather, it signifies that today God's Spirit is intensified seven fold in this age in order to accomplish the completion of His purpose.
But unto us God revealed them through the Spirit: for the Spirit searcheth all things, yea, the deep things of God. (1 Cor. 2:10)