Jesus Christ identified four tendencies that undermine faith in statements where He chided others with the phrase "O you of little faith." These are:

Worry

Jesus said God would take care of our needs, cautioning: "Do not worry . . . Now if God so clothes the grass of the field [splendidly], which today is, and tomorrow is thrown into the oven, will He not much more cloth you, O you of little faith? Therefore do not worry . . . But seek first the kingdom of God and His righteousness, and all these things shall be added to you" (Matthew 6:25-33).

Fear

While on a boat in the middle of a storm, the disciples woke Jesus and pleaded that He save them from drowning. He answered, "Why are you fearful, O you of little faith?" Then He rebuked the sea and it immediately grew calm (Matthew 8:23-26).

Doubt

Peter saw Jesus walking on the water of the Sea of Galilee and asked if he could do the same. Jesus invited him to join Him, and Peter, too, began walking on the water. "But when he saw that the wind was boisterous, he was afraid" and began to sink (Matthew 14:30). Christ "stretched out His hand and caught him, and said to him, 'O you of little faith, why did you doubt?'" (Matthew 14:31).

Human reasoning without spiritual understanding

Jesus warned His disciples, "Take heed and beware of the leaven of the Pharisees and the Sadducees" (Matthew 16:6). He was cautioning them against the wrong teachings of these religious leaders (Matthew 16:12), but the disciples initially thought He was talking about the physical leavening of bread since they had not brought any bread with them (Matthew 16:7). Jesus responded, "O you of little faith, why do you reason among yourselves because you have brought no bread?" (Matthew 16:8). He then said that they wouldn't have missed His point if they'd kept in mind that He could miraculously provide physical bread if there was a need, having done so to feed thousands on two occasions (Matthew 16:9-11).