Sometimes you need to forget your theology
No one can have two masters. MANY choose to serve their creeds rather than a person. But they are really trying to serve themselves and their own personal desires - the doctrines they love. You either love you yourself and your doctrines and serve them or you serve Jesus Christ the word of God. No one can have two masters or he will love the one and hate the other.
It is easy to see what people really love. You will know them by their fruits.