"For, brethren, ye have been called unto liberty; only use not liberty for an occasion to the flesh, but by love serve one another. For all the law is fulfilled in one word, even in this; Thou shalt love thy neighbour as thyself. But if ye bite and devour one another, take heed that ye be not consumed one of another. This I say then, Walk in the Spirit, and ye shall not fulfil the lust of the flesh."
The churches in Galatia had been flooded with a great deal of false teaching about grace and the law, so when Paul wrote the epistle of Galatians to them, he included a great deal of instruction about godly Christian living. One of the most important things he told them, and us, is that we must be filled with and walking in the power of the Holy Spirit to live as God commands us to live. Though the Holy Spirit is present in the life of each believer, He is not in control of each believer. That depends on our willingness to yield to and obey Him.
Our ability to overcome sin depends utterly on God's power. Any time a Christian is sinning, it is evidence that the Holy Spirit is not in control. Most parents and grandparents have had the experience of placing a young child's hands on the steering wheel of a car and letting them “drive.” The child is not the one in control, and if he or she was, it would lead to disaster. The hands of the adult are guiding the car and making sure it goes where it should.
In the same way, we must allow the Holy Spirit to be in control of our lives. If we take matters into our own hands, disaster is sure to follow. Only when we walk as He directs can we be certain that we are on the path God intends for us to walk.
When we are filled with and controlled by the Holy Spirit, sin holds little attraction and has less power.