Andrew, thanks. this is useful up to a point, especially where you state: "The idea of incarnation does not require a virgin birth; nor did the story of the virgin birth arise out of belief in the incarnation."

interestingly you also state that an immaculate conception was not needed in order for Jesus to be sinless. i’m not closed to this possibility, even though it goes against the mainstream teaching that He had to be born of a virgin due to sin coming through the seed of the father and the world in need of a sinless sacrifice for eternal atonement.

if Jesus had in fact been born of two biological parents - with no direct divine involvement - how would he have escaped the inheritance of sin?