These verses teach something wonderful! They explain our need and "our God given ability" to learn to make use of God's Spirit. Until he lost faith, Peter used the Spirit to walk on water. When he sank, Jesus said "O you of little faith." Jesus said our faith can do anything we need. (
Mat 21:21-22) Peter learned to do better after Christ was killed and resurrected. (
Acts 3:11-16)