John 5:38

And ye have not his word abiding in you
Which some understand of Christ himself, the Logos, or word: who, though he was now with them, being made flesh, and dwelling among them, yet would not long continue with them: though rather this designs the written word, or the Scriptures of truth; and especially that part of them, which contains prophecies concerning the Messiah, which did not dwell in them richly, nor they dwell in their meditation on them, as was requisite. Or rather, it may intend that word of God expressed in the testimony he bore to the sonship of Christ at his baptism, by a voice from heaven, which made no lasting impression upon the minds and hearts of the Jews that heard it; as appears by what follows:

for whom he hath sent, him ye believe not;
meaning himself; for if they had had either a due regard to the sacred oracles, or to that voice from heaven at his baptism, they would have received and embraced him as the Messiah, and sent of God, and not have disbelieved and rejected him, as now they did.