Jesus quotes a verse from Deuteronomy as the greatest commandment.
# with all your heart, with all your soul
The idiom "with all ... heart" means "completely" and "with all ... soul" means "with all ... being." See how you translated these two phrases in [Deuteronomy 4:29](../../deu/04/29.md). (See: [[rc://en/ta/man/translate/figs-idiom]])
Here "great" and "first" mean the same thing. They emphasize that this is the most important commandment. (See: [[rc://en/ta/man/translate/figs-doublet]])