My two older sons attend a Jesuit high school, so we are familiar with the spirituality of St. Ignatius of Loyola, the founder of the Jesuits.
Ignatius was a soldier who was seriously wounded. During his recuperation, he experienced a time of conversion and contemplation. He then sought to imitate Jesus and encouraged others to try to learn of Christ’s priorities for them.
One of the things he said was
Few souls understand what God would effect in them if they should give themselves entirely into his hands and allow his grace to act.
To me this says that it is our own hesitation which is holding us back from truly doing what God wills. And if we would overcome our fear and doubt, God could completely change us, fill us with His grace, and use us in the world.