Krishna now opens a new section. Even the food a person prefers, he says, is of three kinds. The same goes for sacrifice, austerity, and charity — each comes in three varieties.
This is a remarkably practical teaching. Krishna is connecting something as everyday as diet to the gunas. The food a person gravitates toward shapes the mind, and the mind shapes everything else. What ends up on the plate is never just about taste.
Krishna tells Arjuna: listen, and I will explain the difference between all of these. The shlokas that follow will classify food (17.8-10), sacrifice (17.11-13), austerity (17.14-19), and charity (17.20-22) — each into its sattvic, rajasic, and tamasic form.