There are many things that try to steal our attention and focus away from God. One of the hardest battles to face as a Christian is the battle of the mind. I believe Satan can begin to infiltrate our minds if we do not have a defense system in place.
The more controlled your mind is, the easier it is to remain focused on God. Living in this world and trying to live for Christ at the same time is almost considered an oxymoron. The reality is that Christians live this oxymoron on a daily basis.
It is necessary to develop defenses to guard your mind on a daily basis.
God desires not for us to conform to the standards of the world, but to live serving Him and others. It is hard to live for God if your mind is filled with things that are not honoring to God.