Matthew 6:24 KJV
24 No man can serve two masters: for either he will hate the one, and love the other; or else he will hold to the one, and despise the other. Ye cannot serve God and mammon.
Many people believe they can make everyone happy. They can attend church on Sunday and partially live by biblical standards and they can live how the worlds says the rest of the time. However, there is no way to be truly successful doing that. If someone tries to do that, they will encounter many times when they will have to choose one way over the other; thereby choosing their true loyalty.