Have you ever idealized the past so much that you forget God's faithfulness? Numbers 14 shows that this mindset caused the Israelites to rebel against God.
The people whom God has called must be sanctified in order to reflect His holiness. The book of Exodus told the story of God redeeming the Israelites and calling them to be a holy nation. Now, Leviticus represents a guidebook for the new nation of Israel.
Sometimes things don't go exactly as we imagine them going. However, God is faithful. We must trust and hope in Him, looking to Him alone for the provision of the Good.
The failure and stubbornness of people in the past didn't prevent God accomplishing His purposes, and it wasn't going to stop Him now. Moses self-perceived deficiencies did not matter. If God calls you to a purpose, He will equip you for it.
In an amazing turn of events, God sovereignly guided the process to preserve Moses' life. It would be through Moses that God would deliver his people from bondage.
Exodus 1 describes how the children of Israel came to be oppressed by the Egyptians. However, God did not abandon them and was with them during their bondage.