Christians cannot commit the sin of blasphemy against the Spirit. Or, as is referred to as the Unpardonable Sin. And, one thing for sure - if you are worried that you have committed it - that is a good sign that you haven't. It is a conscious resistance and decision against the Holy Spirit of God.
However, we as Christians have all been guilty of "quenching the Spirit" as the Apostle Paul warns us against in 1 Thessalonians 5:19. I like the translation in the Holman Christian Standard Bible, it says, "Don’t stifle the Spirit." The Amplified Bible helps us understand this as it renders this verse as, "Do not quench (suppress or subdue) the [Holy] Spirit...." As I was reading this last week, I came across this quote by Anglican Bishop Dr. Handley Moule. He said, "The difference between someone who is quenching the Spirit and someone who is allowing the Spirit to have free course in their life, is the difference between a well in which there is a spring of water choked, and a well in which the obstruction is removed so that the water springs up and fills the well."*
If we allow fears, self-centered expressions, self-centered thoughts, and self-centered minds to control our lives, then we will find that we are stifling the Holy Spirit of God. The danger today in our churches is not that we are going to be "Boiling Believers," but that we will be the "Frozen Chosen." Let us today seek to find what obstacles are in our "wells" of life and remove them so that the "Water of Life" can freely flow through us.