Often Christians will give counsel to let the peace be your referee when making a difficult or important decision. I often hear Christians say things like, "I feel or don't feel peace about ___________." Many fleshly decisions survive masked under this "spiritual" counsel. In fact, the Bible gives at least one biblical example of someone who was totally at peace with rebellion against God's revealed will. He followed the peace in his heart which leads him the complete opposite direction from God's will. This man is Jonah, he was given a direct biblical command to go to Nineveh, but what does he do? Jonah gets on a ship headed to Tarshish, the complete opposite direction. And the real kicker is that he is so at peace with his sin that he falls into a "deep sleep" in the middle of a raging storm (Jonah 1:5-6).
I think it is often normal for Christians to not feel peace about doing God's will. Dealing with the anxieties in our heart goes along with growth in the faith and is an essential part of trusting in God's commands and principles. Do you think Jesus was at total peace when he was sweating blood in the Garden? The peace He felt did not come from a fleshly felt peace, it was peace in doing what was obedient to God the Father.
As a Pastor, I have had to church discipline at least three members all the way to the last step of Matthew 18, and I didn't always feel very peaceful about it. But I knew it was what God had commanded in Matthew 18. I remember two days before we had to remove a friend of mine from our fellowship, I was feeling anxious about the whole thing! But my wife's grandfather told me a story about his pastor doing church discipline; he said, "You have to be faithful to what God says, kick them out, and God will send you three to replace the one." And you know the funny thing was in that business meeting we voted one out and in the same meeting voted three into our fellowship! Praise God!
The feeling I had during the whole thing felt more like a brick in my stomach, but doing what is right (that is what is biblically commanded) is usually not what is easy, at least at first! So don't trust the peace feelings in my heart or yours! Our hearts are desperately wicked and who can know them (Jeremiah 17:9)? If we follow them, we will most likely end up like Jonah, in a dirty, fishy, smelly situation wishing we had done what God asked the first time! In the end, Jonah still did what God commanded, he did it with whale puke all over him. So our referee is not our fickle feelings, but our referee remains the objective, unchanging, inerrant, infallible, revealed Word of God!