I dont know how someone might separate the words of Jesus Christ from Christ since the words of Christ were God the Fathers words we were to hear. The word Jesus had spoken John 12:48 would be that which judges the one that receives neither him or his words.
For example, God testifies through Moses here of Him
Duet 18:18 I will raise them up a Prophet from among their brethren, like unto thee,
and will put my words in his mouth; and he shall speak unto them all that I shall command him. (Acts 7:37)
Even as Jesus had said,
John 12:49 For I have not spoken of myself; but the Father which sent me,
he gave me a commandment, what I should say, and what I should speak.
He spake by God's commandment, His words are of great importance (as is noted in Moses)
And concerning his words He continues,
Duet 18:19 And it shall come to pass, that whosoever will not hearken unto my words
which he shall speak in my name, I will require it of him.
Confirmed also by the Apostles
Acts 7:37 This is that Moses, which said unto the children of Israel,
A prophet shall the Lord your God raise up unto you of your brethren, like unto me;
him shall ye hear.
Jesus also confirming what Moses wrote of him
John 5:47 But if ye believe not his writings, how shall ye believe my words?
And according to the same written in Duet 18:18-19 Jesus says
John 12:48 He that rejecteth me, and receiveth not my words, hath one that judgeth him:
the word that I have spoken, the same shall judge him in the last day.
As Jesus again confirms the words he spoke were given him (and then to them)
John 17:8 For I have given unto them the words which thou gavest me; and they have received them,
and have known surely that I came out from thee, and they have believed that thou didst send me.
Then he prays for them who received His words
John 17:9 I pray for them: I pray not for the world, but for them which thou hast given me;
for they are thine. (John 8:47)
John 8:47 He that is of God heareth God's words
But he does not pray for them alone
John 17:20 Neither pray I for these alone, but for them also which shall believe on me through their word;
And when others receive the same, they do write saying,
1 Thes 2:13 For this cause also thank we God without ceasing, because, when ye received the word of God which ye heard of us, ye received it not as the word of men, but as it is in truth, the word of God, which effectually worketh also in you that believe.
The gospel is the power of God unto salavtion to them that believe.
Romans 1:16 For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek.
Being ashamed of me and of my words are shown equally
Mark 8:38 Whosoever therefore shall be ashamed of me and of my words in this adulterous and sinful generation; of him also shall the Son of man be ashamed, when he cometh in the glory of his Father with the holy angels.
His words are what we have heard which should abide in us and we also will continue in the Son and the Father
1 John 2:24 Let that therefore abide in you, which ye have heard from the beginning. If that which ye have heard from the beginning shall remain in you, ye also shall continue in the Son, and in the Father. (2 John 1:9)
Not to be ashamed of him and his words that the Son of man be not be ashamed of them, John says,
1 John 2:28 And now, little children, abide in him; that, when he shall appear, we may have confidence, and not be ashamed before him at his coming.
So if we love Jesus (we will keep his words) not separate Jesus from his words
John 14:23 Jesus answered and said unto him, If a man love me, he will keep my words: and my Father will love him, and we will come unto him, and make our abode with him.
2 John 1:9 Whosoever transgresseth, and abideth not inthe doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son. (1 John 2:24)
As Jesus said them, My doctrine is not mine, but his that sent me. John 7:16
And again,
John 17:8a For I have given unto them the words which thou gavest me; (Duet 18:19)
and they have received them
And Hebrews, giving the more earnest heed to the things we have heard
Heb 2:1 Therefore we ought to give the more earnest heed to the things which we have heard, lest at any time we should let them slip. (See Heb 2:1-4)
Just seems to put equal weight on Him (the Christ, the Word made flesh) and His words (He spake by commandment) and yet the word that He (the Word) had spoken would be that which would judge them.