Sabbatarianism is usually defined as the belief that Christians should observe a particular day of the week as the Sabbath, either the seventh day or the first day of the week. This means more than simply attending church on the weekend. On their Sabbath, Sabbatarians refrain from all customary work, except works of charity, necessity and worship, because they understand the Sabbath to be a law of God. They do so even if it means economic hardship, shunning or persecution.