True belief will always spur people into action. The other side of this statement follows that lack of action can often be rooted in some level of disbelief.
The book of John demonstrates how Jesus himself was a man of action who led disciples and performed miracles based on the mental assent and spark of belief from human vessels. Andrew believed, testified to Peter, who then believed and followed Jesus. Philip too testified of his belief in Jesus, an action that drew Nathaniel to follow Jesus.
When Jesus encountered the Samaritan woman at the well did not understand at first who she had encountered, once she believed, she returned to tell others of the man called Jesus, the Messiah. Action.
What is your belief spurring you into? If it is not action, if the extent of your belief is a simple verbal assent, wanting action, then your belief is incomplete.
The book of Acts further demonstrated how, even after Jesus was no longer present in body, his presence through the Holy Spirit spurred multitudes into action. First, those that believed were baptized as Jesus had commanded his disciples to do (Matthew 28:19). The gift of the Holy Ghost was given to those repentant and believing people. And many signs and wonders continue to follow those who believe, obey his Word, and call on the name of Jesus.
Two final thoughts on belief. In the midst of his teaching on faith in action, James writes, “Thou believest that there is one God; thou doest well: the devils also believe, and tremble.” Thankfully, Jesus doesn’t require much of us. Matthew records Jesus saying, “Because of your unbelief: for verily I say unto you, If ye have faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place; and it shall remove; and nothing shall be impossible unto you” (Matthew 17:20).
Be encouraged, believe, and challenge your faith to act in obedience to God’s Word.