Let me give you an example.
John 2:23-25 King James Version (KJV)
23 Now when he was in Jerusalem at the passover, in the feast day, many believed in his name, when they saw the miracles which he did.
24 But Jesus did not commit himself unto them, because he knew all men,
25 And needed not that any should testify of man: for he knew what was in man.
He was referring to the spirit of man being in man that does not know the things of God, as it is written:
For what man knoweth the things of a man, save the spirit of man which is in him? even so the things of God knoweth no man, but the Spirit of God.
If you profess Jesus without the holy Spirit, what you are in truth doing is lying.
That's why the scripture says that no man can say that Jesus is the Lord but by the Holy Ghost..
John 5:31-32 King James Version (KJV)
31 If I bear witness of myself(MAN), my witness is not true.
32 There is another that beareth witness of me; and I know that the witness which he witnesseth of me is true.
John 7:18 King James Version (KJV)
18 He that speaketh of himself(MAN) seeketh his own glory(PRAISE): but he that seeketh his glory that sent him, the same is true, and no unrighteousness(LIE) is in him.
John 2:23-25 King James Version (KJV)
23 Now when he was in Jerusalem at the passover, in the feast day, many believed in his name, when they saw the miracles which he did.
24 But Jesus did not commit himself unto them, because he knew all men,
25 And needed not that any should testify of man: for he knew what was in man.
He was referring to the spirit of man being in man that does not know the things of God, as it is written:
For what man knoweth the things of a man, save the spirit of man which is in him? even so the things of God knoweth no man, but the Spirit of God.
If you profess Jesus without the holy Spirit, what you are in truth doing is lying.
That's why the scripture says that no man can say that Jesus is the Lord but by the Holy Ghost..
John 5:31-32 King James Version (KJV)
31 If I bear witness of myself(MAN), my witness is not true.
32 There is another that beareth witness of me; and I know that the witness which he witnesseth of me is true.
John 7:18 King James Version (KJV)
18 He that speaketh of himself(MAN) seeketh his own glory(PRAISE): but he that seeketh his glory that sent him, the same is true, and no unrighteousness(LIE) is in him.