Isn’t it good when children obey their parents? If you tell your child to clean his/her room, for instance, aren’t you happy when they do it? And when you ask them to do it, it is not a, "if you want to", but you really expect it to be done. When it’s not, there are many emotions that overtake your body.
The Apostle Paul wrote to Philemon and said, "Having confidence in your obedience, I write to you, since I know that you will do even more than what I say" (Philemon 21 NASB). Did you notice Paul had confidence he would be obedient? In this letter, he is telling Philemon to accept back the runaway slave, Onesimus, as a brother for he was useful to him now.
Why do we not obey the things we should do? I can’t exhaust all the reasons here but let me mention a few. One of the reasons is because of pride. Someone described this as a five letter word with "I" in the middle. We are too proud to admit we need to surrender to someone else. We want to do things our way and that may not be the way that is best.
Perhaps we don’t obey because of disappointments. We did obey in the past, but we did not receive the results WE expected, and since we have been disappointed before, why try? We live with disappointment every day. Sometimes it is beyond our control (other people, our health, etc). Sometimes we may have done something that was wrong and caused it ourselves. After enough of this, it is easy to "go our own way" instead of surrendering.
Then, we may be jealous or envious. Why should I obey when someone else got what I wanted? This is ugly. Many people feel that someone has something they want, and if I can’t have it, I will not be happy that others do either. As a matter of fact, the idea is, I just will do what I want.
As people who want to follow God, we are called to surrender. Jesus said if we would be His disciple we must deny self, take up our cross and follow Him (Matthew 16:24). There is no room for pride here. Someone may object, "Why should I do what Jesus says?" In order to be His follower. And if we don’t follow Jesus, we follow Satan.
Paul was confident that Philemon would obey what he had asked. I believe he did. Are we willing to surrender our pride, jealousies and everything that would keep us from Him? I’m confident you will do the right thing.