An excerpt from "Got Questions.org" entitled, "What is a measure of faith (Romans 12:3)?" states: "God has given to each a “measure of faith” to use for Him. This “faith” is the gift from which all the other gifts flow. Faith is the first gift we receive (for justification), and faith is the gift that brings the other gifts of the Spirit into our lives. When a person is born again, God gives him gifts as a new member of the family of God. We receive the gifts according to the measure that God has given us, and we exercise the gifts according to the same measure of faith." This article may be viewed at: What is a measure of faith/gotquestions.org
Reference: Romans 12:3