Deuteronomy - Chapter 13

In this chapter the people are told to put God first:

“Suppose someone secretly entices you—even your brother, your son or daughter, your beloved wife, or your closest friend—and says, ‘Let us go worship other gods’—gods that neither you nor your ancestors have known. They might suggest that you worship the gods of peoples who live nearby or who come from the ends of the earth. But do not give in or listen. Have no pity, and do not spare or protect them. You must put them to death!"

Jesus says a similar thing about putting him first (in Matthew 10)

“Don’t imagine that I came to bring peace to the earth! I came not to bring peace, but a sword. I have come to set a man against his father, a daughter against her mother, and a daughter-in-law against her mother-in-law. Your enemies will be right in your own household!’ If you love your father or mother more than you love me, you are not worthy of being mine; or if you love your son or daughter more than me, you are not worthy of being mine.  If you refuse to take up your cross and follow me, you are not worthy of being mine."