"Whosoever shall confess that Jesus is the Son of God, God dwelleth in him, and he in God."
1 John 4:15
If we confess that Jesus is the Son of God, God will forever be in us! But if we do not confess that, how God be in us? It's like taking an oral speech test in speech class. The assignment is to speak out and let others hear us but if we do not speak out for our speech teacher (God) how can we pass our speech test? We must declare our Lord and Savior.