Chapter 16:
This is the second time recently Moses has fallen facedown. Is he trying to show humility to the men accusing? Is what they accuse him of a sin and he wants God to not be offended?
Ted: I think that, from past experience, Moses knew that when anyone came against him (which means that they were rebelling against God), God often would punish them, sometimes with death. Therefore, instinctively, he fell facedown before God, knowing that doing so would be the only chance of pleading for the lives of the people (as in Numbers 16:22,45).

I suspect that Moses' great humility had something to do with it as well. In effect, what he was doing was humiliating himself before the people--which did not matter to him, if there was some chance that they could be saved from God's wrath. Moses was a "type" of Jesus, Who did the same for our salvation.

Chapter 17:
These people are retarded. They continually choose to doubt God and believe the opposite of what He says. I cannot understand it, because they have seen Him and continue to see Him and His works every day.
Ted: You hit the nail on the head of one of the most profound mysteries of the Bible and of mankind. Today, many people would say, "If God were to show Himself to us, we would believe in Him and follow Him!" Not so. The stiff-necked, rebellious Israelites, wandering in the desert, were examples to us of how distorted the heart of humankind really, truly is.

The Israelites knew that God was with them, and they had observed God destroying many of them for being disobedient. In their "heads" they knew better than to rebel; but their evil hearts deceived them into thinking that they were "above the law." As the great prophet has written, "The heart is deceitful above all things and beyond cure. Who can understand it?" (Jeremiah 17:9).

Even in the time of Jesus, the Israelites were the same; most of them had not changed a bit. Jesus told them, "Has not Moses given you the law? Yet not one of you keeps the law" (John 7:19). To those who asked Jesus to tell them plainly if He were the Christ (Messiah), He said, "I did tell you, but you do not believe. The miracles I do in my Father's name speak for me, but you do not believe because you are not my sheep" (John 10:24-26). The people witnessed Jesus' miracles, just as the ancient Israelites saw God firsthand; but they still refused to put their faith in Him.

The Israelites in the desert who, astoundingly, rebelled against God were not His "sheep." Essentially, they had been chosen or "predestined" to fail. As God wrote through another great prophet, "Be ever hearing, but never understanding; be ever seeing, but never perceiving. Make the heart of this people calloused; make their ears dull and close their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts, and turn and be healed" (Isaiah 6:9,10).

Remember that, back in Egypt, God caused Pharaoh's heart to be hardened, and Pharaoh chose to harden his own heart. In a similar manner God caused the majority of the Israelites to be blind and deaf to the truth and caused their hearts to be calloused, and they themselves chose to turn away from the truth. This supports my belief that predestination and free will both are true and take place at the same time; there is a one-to-one correspondence between them (see Which do you feel is true: God's predestination or our free will?).