When Christians offer arguments for the existence of God based on the beginning of the universe or the objective nature of morality, some atheists will respond by asking, “Why can’t we just say we don’t know what caused the universe or what the objective source of morality is?” How might a thoughtful Christian respond?

I would suggest that you turn the question around. Ask them, “Why can’t we just admit that God best explains the origin of the universe and the objective nature of morality?” The atheist wants to plead ignorance, but we are not ignorant on these matters. It’s not as if we don’t know what the options are. We do. And it’s not as if the evidence is equal for all options. We have solid scientific, philosophical, and logical evidence that points to God as the cause of the universe and ground of morality. In other words, we have knowledge, not ignorance. So why not just say we don’t know? It’s because that would be a false statement. We do know. The evidence clearly favors the theistic hypothesis.