Laws have several purposes.
The two are easily confused and often abused-people sometimes use one or the other to justify their actions. But if the laws of the land conflict with the laws of God, we obviously must choose to obey God's laws first. However, one must still worship and serve God regardless. If you find yourself in such a situation where you must choose, it might be wiser just to leave the country and go somewhere you can worship freely. Or you can pursue actions to change the law, such as voting.