Is that little voice in your head God, or is it just a mild case of Multiple Personality Disorder (MPD)? People ask me a lot, "How do you hear God speak?" and "How do you know when it's God and not your own thoughts or Satan?"
Excellent questions! First, consider this verse:
"But solid food is for the mature, who because of practice have their senses trained to discern good and evil." Hebrews 5:14 (NASB)
I think of learning to hear God speak like this: When I was a newborn baby, I'm confident my parents looked at me and said something like, "Isn't she the most adorable little thing?" Dad probably said, "She looks just like your side of the family, honey (I had thick black hair and colossal bunions)" Mom said, "No, she definitely takes after your side (I also had skinny bird legs and huge triceps). Anyhow, they probably oohed and aahed over me for hours. Did I even hear them? Did I know they were talking to or about me? I don't think so. My senses hadn't developed enough to know I was even being spoken to.
Fast forward 3 months. In my crib I hear noises but it sounds like, "Blah blah blah blah…" I can't understand communication, but now I can at least look in the direction of the noise, showing that I'm aware of the source of noise. It could be coming from anything-even the T.V. repair guy for all I know.
6 months later…this is what I hear. "Blah…blah…NO! Blah blah mommy says…blah blah." So I'm learning how to recognize bits and pieces but I still only get a very small portion of what she's saying to me. But by now, I'm beginning to be able to distinguish who is talking–sweet mom's voice, or big strong daddy's voice (I got his triceps, remember?) or mean old jealous brother (oops, didn't mean to compare my brother to Satan).
And so the progression goes, until I have grown up into a language that I perceive, hear, and understand. I know WHO is talking, and WHAT they are saying.
It's a lot the same with God. I LEARN to hear Him speak. I have, through trial and error, through exposure and following the different voices (God, my own flesh, and Satan) had my senses trained to discern the difference. And just like in this life, my parents aren't always talking to me, but I still recall their words often. It's the same with God. He doesn't speak constantly to us, but often times He expects us to go back to what He told us before–to keep His words echoing in our hearts when He is otherwise silent.
So here's an example of my journey…when I was a kid, I was never aware of God speaking (looking back, I see that He was). In college, I had my first conscious experience where I knew without a doubt I heard His voice. In my twenties, I heard him periodically and the rest of the time I imagined He was mad at me, since He was so quiet. In my thirties, I learned that when He's silent, He's not mad, He just doesn't have anything special to say to me right then. Actually He's teaching me to walk in faith and stay devoted to Him even in His silence. But He's still right there, listening to me and working in my life, regardless if I perceive Him or not. But nowadays, in my just barely "ahem" 40's, I hear Him frequently, because my senses are now quite trained to perceive His voice.
How does He speak to me? Mostly through His Word, or in my thoughts as sort of a foreign thought or idea dropped into my thinking (Satan speaks this way too, be careful). Sometimes through other people. Often through nature. A few times through dreams.
Learning to discern when it's His voice or your own or Satan's is just a skill that comes over time with lots of practice. The best advice is that, if you think God is telling you something is going to happen, write it down and wait. Don't tell anyone, just keep it between you and God and see if it happens. If you think God is telling you to DO something, ask Him to confirm it. In my experience, He always confirms something He wants me to do, unless it's a no-brainer commandment already (like loving people, duh!). If you want to do a certain thing but you're not sure what God wants you to do, ask Him to close the door if that is not what He wants you to do. Otherwise, step carefully through it.
I could write a book on this topic and it's not a three-step process, so exercise lots of caution, but know this: God wants to speak to you and He wants you to learn to hear it.