There are many scriptures that speak of varying degrees of faith. However, the scriptures also speak of Jesus increasing in wisdom (Lk. 2:52) that certainly refers to His physical intellect drawing more and more on the perfect wisdom of God that was already in Him at birth. It is in this way that we also increase in faith.
At salvation, the believer is given the supernatural faith of God. We had to use the very faith of God (not human faith) to believe the gospel (Eph. 2:8).
That faith came to us through hearing the Word of God (Rom. 10:17), and once we are born again, it becomes an abiding fruit of the Spirit within us.
Every believer is given the same measure of faith at salvation but not all believers use what God has given them. Therefore, it is correct to speak of growing in faith and having great faith or little faith, but it is important to understand that this is speaking of how much faith we use or manifest – not how much faith we were given. All believers were given ‘the’ same measure of faith.
Jesus’ example of the grain of mustard seed underscores the truth that our faith is sufficient if we will just use it without the hindrance of unbelief.
He then continues on into the parable of the servant serving his master to illustrate that our faith is not the problem but rather our use of it. We are using it to serve ourselves instead of our master who is God.
Living by faith is not something special that only the ‘super-saints’ are supposed to do. The Lord expects all of His children to live a supernatural life of faith. He gave you everything you need to do this, just let Him live through you.