Confidence in God
The more we trust in God, the more he will act in our lives.
This confidence or trust includes the theological virtues of faith and hope. Faith is defined as, "The theological virtue by which we believe in God and believe all that he has said and revealed to us, and that Holy Church proposes for our belief, because he is truth itself (CCC 1814)."
Hope is a little different: "Hope is the theological virtue by which we desire the kingdom of heaven and eternal life as our happiness, placing our trust in God's promises and relying not on our own strength, but on the help of the grace of the Holy Spirit (CCC 1817)." The theological virtues comes from God, are infused in us by sanctifying grace, and leads us to God.
When performing a healing, Jesus often tells the people that it was because of their strong faith that they were healed. Conversely, Jesus did not perform many miracles in his home town because of their lack of faith (Mt 13:58). Jesus is often very demonstrative in his praise for those of great faith and his condemnation for their lack of faith. There is a direct correlation between one's faith and the grace of God that is manifested in that person's lives. Jesus tells us that with faith we can move mountains.
Scripture tells us:
'Trust in the Lord with all of your heart lean not on your own understanding. In all of your ways acknowledge him and he will make your path straight." (Pr 3:5-6)
Mary was filled with faith. St. Augustine said that Mary conceived Jesus in her heart by faith before she conceived him in her womb. Elizabeth, filled with the Holy Spirit, cried out, "Blessed are you who believe that what was spoken to you by the Lord would be fulfilled." (Lk 1:45)
Jesus tells St. Faustina: "The graces of my mercy are drawn by means of one vessel only and that is trust. The more a soul trusts, the more it will receive." (1578). Trust is so important that Jesus had St. Faustina put the following at the bottom of the Divine Mercy image: "Jesus, I trust in you!"
Faith is a gift, which requires a reception and a response. The more we make acts of faith, hope and love, the more graces we will receive and grow in the theological virtues.