I ran across this relevant passage from Josephus which I had not noticed or thought of before.
18.116] Now some of the Jews thought that the destruction of Herod's army came from God as a just punishment of what Herod had done against John, who was called the Baptist.
[18.117] For Herod had killed this good man, who had commanded the Jews to exercise virtue, righteousness towards one another and piety towards God. For only thus, in John's opinion, would the baptism he administered be acceptable to God, namely, if they used it to obtain not pardon for some sins but rather the cleansing of their bodies, inasmuch as it was taken for granted that their souls had already been purified by justice.
[18.118] Now many people came in crowds to him, for they were greatly moved by his words. Herod, who feared that the great influence John had over the masses might put them into his power and enable him to raise a rebellion (for they seemed ready to do anything he should advise), thought it best to put him to death. In this way, he might prevent any mischief John might cause, and not bring himself into difficulties by sparing a man who might make him repent of it when it would be too late.
[18.119] Accordingly John was sent as a prisoner, out of Herod's suspicious temper, to Machaerus, the castle I already mentioned, and was put to death. Now the Jews thought that the destruction of his army was sent as a punishment upon Herod, and a mark of God's displeasure with him.
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Jewish Antiquities
Josephus on John the Baptist
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The thinking of John might just have some similarity to the thoughts of Jesus.(that would be same ball park not so much exact correspondence)