I would disagree. Pretty much any classic literature has Christian themes.
The Iliad does not have child sacrifice in it. I just finished reading it two weeks ago. The only event in the Iliad involving something like human sacrifice was when Achilles killed 20 Trojan captives (young men) at the tomb of Patroklus. Agamemnon may or may not have killed his daughter Iphigenia; there are two versions of the story (in one, she is killed; in the other, Artemis substitutes a doe for Iphigenia and spirits the girl away to Egypt). However, that story was not in the Iliad. Furthermore, Agamemnon was a weak and foolish king who met a nasty fate (his wife murdered him with an ax) after he defied the gods time and time again. "Do not defy the gods (or God)" is a Christian theme.
Even more so, Achilles-one of the main characters of the Iliad-stood firm on his principles. The Trojan War was fought to return a wife (Helen) to her husband. If one is fighting for this cause, you have a real problem on your hands when your king does the same thing. Even though Agamemnon was fighting to return Helen to Menelaus, Agamemnon stole Briseis from Achilles. Achilles said several times that he was going to marry Briseis and loved her. Achilles refused to fight for a king who didn't believe in the cause for which they were fighting. However, when Achilles was told by the gods to fight, he IMMEDIATELY obeyed them. No argument, no putting it off. Athena showed up and told him to fight, and Achilles said, "So be it." Immediate obedience is a Christian virtue.
When Priam (king of Troy)went to the tent of Achilles to ask for the body of his (Priam's) son Hector (greatest Trojan warrior who killed Achilles best friend and was killed by Achilles) back, Achilles had compassion on him. Indeed, they wept together over the many deaths. Achilles had Hector's body washed and wrapped in fresh linen, and was so kind to Priam that he caused Priam to exclaim, "I have gone through what no other mortal on earth has gone through; I put my lips to the hands of the man who has killed my children."
Story A (Iliad) is moral because it holds certain virtues (obedience to the gods, reverence for the gods, standing for what is right, compassion, forgiveness) in high esteem. Story B is immoral because it holds vices (killing helpless people so that they and particularly the people around them don't have to go through pain, extramarital sex, lewdity,promiscuity, blasphemy, etc., etc., etc.) to be the norm and, indeed, to be good.
What's this I see???? Well-frosted Egyptian cookies! Nice work. Always a pleasure to see such demolition of even the theory that he might have even read, much less comprehended, Homer. Some deficiencies in my own education seem to have been complemented away by strengths in yours. Thanks for the help.