I saw a neat billboard over the weekend for the Marines: "No applications accepted: only commitments wanted." In the classifieds when someone is selling something, they will often put, "Only serious inquiries please." Isn't that what God wants from us? In Matthew 23:27, Jesus tells of His disdain for people who are wishy-washy or hypocrites: "You are like whitewashed tombs, which look beautiful on the outside but on the inside are full of dead men's bones and everything unclean." What good are bones? They aren't. When you see the bones of something, its an indication of death; they don't do anything except sit there and continue to rot. Jesus is basically saying we are no good to Him if we are not committed. You are either a child of God or not. There is no kind of-sort of-maybe not-really to it.
Christianity is not ala-carte. Although it may be easier sometimes to pick and choose which parts of following God we want to participate it, we don't get the benefit of the blessings if we aren't fully committed. God wants to give us the full meal deal; not pieces and parts.