It is possible that it was, or it can be our own minds, or the enemy.
What did the voice say? Did it align with the Word of God or go against it?
"Dear friends, do not believe every spiit, but test the spirits to see whether that are from God ... (1 John 4 :1a)
Thanks so much, God bless you
Sharin, as LT said: God will not contradict His Word. First and foremost, the Bible is God's word for us. I have learned not to seek a voice, because Satan can deceive us and seeking a voice can become idolatrous.
However, I have heard an audible Word at times. When I first became a Christian, Jesus spoke to me very clearly. I learned later that his statement was perfectly in line with scriptural truth. Definitely apply the rule that LT mentioned: test every spirit; as well as every teaching. If anyone says otherwise, they have a spirit of anti-Christ.
One of the best things to do is pray and ask God to shepherd you according to His word, then dig deeply into it. The voice we are to discern is "the voice of truth" as the Bible teaches it. When you sit in church, your mind ought to be discerning what you hear is truth, or not. When you speak with people, you ought to be discerning, is this truth or not?
I remember vividly when I became a new believer: I had been reading and praying frequently and I heard the Spirit of God say to me (very deep in my soul): "Ask me to lead you". So, I began to do that and found the scripture where Jesus says the Spirit will lead you into all truth. So, I began to pray "Lord Jesus, by your Holy Spirit lead me into all truth". and I found that I began to have a supernatural discernment beyond what I had learned or read, which I confirmed by reading and learning to understand scripture.
One day, while in a very dead and ritualistic church, I asked the Lord "why is it when I read your Word at home, you make it come alive, but here in this church I feel like even the leaders don't know you and that you aren't here?" Just as quickly, deep in my soul, I heard "i will lead you where I want you to go". Then, during that week, I prayed again and the Lord said (again, very deep in my soul) "pray until Saturday and I will lead you".
My fiance was not a believer at that point, but she was with me on Saturday and she said "if we have to go to church, can we go somewhere like my friend goes? They are friendly and they seem happy about God. That church you go to is dead as a morgue" Instantly, I said "yes" because I knew the Spirit had already prepared me for that. We looked in the phone book and found a church very much like where her friend went. I prayed and again asked the Lord to guide me - I didn't want to go somewhere bad.
Sunday morning we sat in the church and the Spirit said to me "this is where i want you to go". My fiance accepted Christ that day, during a move of the Spirit after the preaching. I met that Pastor as we left and the Spirit came over me as I shook his hand and I heard deep in my soul "this is my servant". While we were there for several years, that Pastor gave us a deep respect for the word of God. Every week, God would speak to us in a unique way, through the preaching of the word, that confirmed answers to questions we had during that week before. Sometimes, even during the sermon, the pastor would interrupt and say "The Lord has just spoken to me to explain something to you...." and he would mention exactly the thing we had discussed in the car on the way over.
So, yes, you may hear the Lord speak to you. Test what you hear. He wants you to do that. But, understand that his leading will always guide you to pray and listen, in accordance with His Word. Never in neglect of it.