Which brings me to a point about metaphysics.

Can you be good without God? Of course. But that’s a different question from whether or not goodness can exist without God.
The moral ethic of the Enlightenment is basically John Stewart Mill’s harm principle. Do no harm and you’re an upstanding member of the moral community. But this view of virtue is wholly negative, an absence. “Do no harm” is not a positive vision of the good.
- Note: Mm … but what if “do no harm” is more like “don’t act against the grain of the universe”? Then the universe itself is the good we have a vision of.
Only a metaphysical commitment can create that.
Anyone can be good, believer or non-believer. But the good itself, whether we hit the mark or miserably fail, has to be real. That the moral portfolios of Christians and non-Christians even exist points to the existence of God. Good people need Jesus because without God good people cannot exist.
- Note: Either this doesn’t follow, or it’s vacuous. Just because the existence of good people hinges on God’s existence --- what doesn’t? --- doesn