but how can a mortal have an immortal child?
You can't discount the importance of miracles in Christianity (as well as many other faiths).
Here's an excerpt from a simplistic argument in favor of the logical acceptance of the possibility of miracles. We could go deeper into this, but that's probably a topic for another thread.
Logic
Finally, it would be basically illogical to state that miracles cannot occur. This is because in order to logically state that miracles cannot occur, a person must either know all things in the universe so that he can rightfully state miracles cannot occur, or he must have some logical proof why miracles cannot occur, or possess a sufficiently sophisticated knowledgebase to conclude the miraculous cannot occur, etc. Furthermore, it is not enough to state that there is no evidence for the miraculous since a person's experiential base is limited. It may very well be that miracles have occurred and this person is simply not aware of it.
Therefore, at best someone could simply say "I do not believe that miracles occur because (insert reason)." At least this leaves open the possibility that they may occur. And if they might indeed occur, why not have the possibility that Jesus who claimed to be God (
John 8:58 with
Exodus 3:14), who fulfilled Old Testament prophecies (i.e.,
Psalm 22:11-18;
Isaiah 7:14;
9:6,
Micah 5:1-2, etc.), who predicted his own death and resurrection (
John 2:19-21; ), appeared to people after his public execution (
Luke 24:39;
John 20:25-28), did indeed actually rise from the dead? Since the eyewitness accounts have been accurately transmitted to us, would it not be logical to believe the witnesses who described what they saw? It would seem so.
Can miracles occur? Yes, they can because there is a God in the universe.
Miracles cannot happen | Christian Apologetics and Research Ministry