Why did Allah describe the Jews as those who incurred wrath and the Christians as those who went astray? Is this related to the Jews' knowledge of the Prophet's mission (peace be upon him) and the Christians' ignorance of it? And was every Christian aware of the Prophet's advent?

The Jews were described as those who have incurred wrath, and the Christians as those astray. The reason for this is that the Jews knew the truth but violated it, thus deserving wrath. As for the Christians, they went astray from the truth due to ignorance, thus deserving the description of being astray. Both are astray and have incurred wrath, but each group was described by what was more prominent in them.

The Christians were specifically described as astray due to their ignorance of the truth, while the Jews were specifically described as having incurred wrath because they abandoned acting upon the truth after knowing it.