EVEN IF YOU ONLY KNOW A FEW SCALES IN 4 KEYS, YOU CAN USE THEM IN ALL 12!!!!
FOR EXAMPLE...
IN THE KEY OF C MAJOR YOU CAN PLAY THE
REGULAR SCALE, OR THE Em, Am, OR THE 3RD AND 6TH WHICH ARE MINOR IN THE KEY OF C...
JUST APPLY IT TO EVERY KEY...THIS IS HOW YOU USE MUSIC THEORY TO YOUR ADVANTAGE IN GOSPLE MUSIC, OR ANY MUSIC FOR THAT MATTER.. HOPED THIS HELPED YOU OUT...