Hello Prayerful,
Be assured that you have not committed Blasphemy against the Spirit. You're not the Lone Ranger regarding those types of thoughts coming into your consciousness. Remember, the powers of darkness can, for lack of a better word, interject those into your thoughts. I'm sure that everyone reading this has had or is having these same types of issues.
First of all, it is important to understand what Blasphemy of the Holy Spirit is. So let's look at what prompted Jesus to say this:
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Then a demon-possessed man who was blind and mute was brought to Jesus, and He healed the man so that he could speak and see.
23The crowds were astounded and asked, “Could this be the Son of David?”
24But when the Pharisees heard this, they said, “
Only by Beelzebul, the prince of demons, does this man drive out demons.”
25Knowing their thoughts, Jesus said to them, “Every kingdom divided against itself will be laid waste, and every city or household divided against itself will not stand.
26If Satan drives out Satan, he is divided against himself. How then can his kingdom stand?
27And if I drive out demons by Beelzebul, by whom do your sons drive them out? So then, they will be your judges.
28But if I drive out demons by the Spirit of God, then the kingdom of God has come upon you.
29Or again, how can anyone enter a strong man’s house and steal his possessions, unless he first ties up the strong man? Then he can plunder his house.
30He who is not with Me is against Me, and he who does not gather with Me scatters.
31Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven.
32Whoever speaks a word against the Son of Man will be forgiven, but
whoever speaks against the Holy Spirit will not be forgiven, either in this age or in the one to come.
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The simple answer is that, since Jesus was casting out demons by the Spirit of God and the Pharisees said that He was casting them out through the power of Satan, then they were calling the Holy Spirit and unclean spirit. Therefore, in order for you or anyone else to commit the sin of blasphemy against the Holy Spirit, you would also have to also make the same claim as the Pharisees did. And I'm pretty sure that you haven't done that.
This is just another one of Satan's tricks by trying to convince you that you have done this in order to make you and others give up your faith in Christ. That fact that you are worried about tells me that the Spirit of God dwells in you and therefore have not committed this. That is unless of course you also believe that Jesus was casting out demons by the power of Satan. Otherwise, you have not committed the unpardonable sin. And that goes for everyone who is reading this who has been concerned about committing the unpardonable sin.