Are we saved by faith or by works? I would say we only need faith, but if we have faith, then we will have works. Here's a parable to explain what it means to have faith in God and why it leads to works.
Let's say that you are flat broke and in debt up to your eyeballs. I, on the other hand, just won millions in the lottery. If I say to you, "I will sell you my winning lottery ticket for $1," you would not need a lot of faith in me to buy the ticket since the cost of faith is low.
Now, let's change the scenario a little bit. Instead of selling you the ticket for $1, I say to you, "If you spend your own time and money to fly across the country and get the ticket from me, you can have it." This is still an incredible deal. Spend $500 to get millions...but would you do it?
You would need to have a lot of faith in me to actually do it. You would have to have faith that I correctly looked up the winning numbers and faith that I am not scamming or tricking you. If you really, truly had faith in me, you would come get the ticket. If you say "I have faith in you," but refuse to come get the ticket, then your actions are betraying your words and showing your true opinion of me.
This is why we are saved by faith, but justified by works. If we truly have faith, it will produce works. "You see that a man is justified by works and not by faith alone." (James 2:24, NASB). Similarly, if we truly have faith and honestly believe Jesus is our savior, we will follow His commandments. "By this we know that we have come to know Him, if we keep His commandments." (1 John 2:3, NASB).
If you claim to have faith in God, what are you doing to show that you have faith?--even a little faith. The more you do, the more your faith will grow. It is no coincidence that Jesus said "The kingdom of heaven is like a mustard seed, which a man took and sowed in his field; and this is smaller than all [other] seeds, but when it is full grown, it is larger than the garden plants and becomes a tree, so that THE BIRDS OF THE AIR come and NEST IN ITS BRANCHES." and then also compared faith to a mustard seed by saying "if you have faith the size of a mustard seed, you will say to this mountain, 'Move from here to there,' and it will move; and nothing will be impossible to you. (Matthew 13:31-32 & Matthew 17:20, NASB).
Paul tells us to examine if we're really Christians (2 Corinthians 13:5). If you claim to have faith in Christ, yet are showing your faith with works (to include obeying his commandments), then do you really have faith? Read these short books and passages to truly examine your life compared to the one we are called to live. 1 John, James, and Galatians 5:16-24 (the fruit of the spirit). It's never too late to turn back to God and starting living out your professed faith.