"The mystical sacrifice of the Phoenicians had these requisites, that a prince was to offer it; and his only son was to be the victim: and as I have shewn that this could not relate to any thing prior; let us consider what is said upon the subject, as future, and attend to the consequence. For if the sacrifice of the Phoenicians was a type of another to come, the nature of this last will be known from the representation by which it was prefigured. According to this, El, the supreme deity, whose associates were the Elohim, was in process of time to have a son, αγαπητον, well-beloved: μονογενη, his only begotten: who was to be conceived (of ανωβρετ), as some render it, of grace: but according to my interpretation, of the fountain of light. He was to be called Jeoud [or יחיר, i.e., only] whatever that name may relate to; and to be offered up as a sacrifice to his father λυτρον, by way of satisfaction, and redemption, τιμωροις δαιμοσι, to atone for the sins of others, and avert the just vengeance of God; αντι της παντων φθορας to prevent universal corruption, and at the same time, general ruin. And it is farther remarkable; he was to make the grand sacrifice invested with the emblems of royalty."
This is why in Sanchuniathon Cronus (El) can have many children and still have a "one of a kind" child to sacrifice. Similarly, in Hebrews 11:17 Abraham's son Isaac is called monogenes in Greek and yahid in Hebrew, when Abraham obviously had a second child, Ishmael.
Thus, an ancient confusion about etymology, translation, and the meaning of culturally-specific terms created the impression that Sanchuniathon's passage about child sacrifice (a well-documented Phoenician practice) was parallel to the death of Christ entirely on the strength of a single word.
This does not change the fact, however, that the sacrifice of royal sons was well-established in the ancient Near East. Even the Bible records such events, including the King of Moab in 2 Kings 3:27, who sacrifices his first born son. The remains of children found in the Phoenician colony of Carthage as well as the widespread reports that Phoenician cultures fed live children to the god "Moloch" indicate that child sacrifice was considered an essential, if rare, aspect of the culture.
Such precedents have led scholars to see in these child sacrifices a background for the sacrifice of Christ. For example, in Pagan Christs (1914), John Robertson made the argument that the sacrifice of Ieoud was a precedent for Christ, and Julian Morgenstern saw this as forming the background for the way Christ was discussed in ancient literature in his Some Significant Antecedents of Christianity (1966).