17.4 'Those who have abundance of Sattva ality and are conjoined with Sattvika faith worship the gods. The meaning is this:  The faith in the worship (sacrifice) of the gods which causes supreme joy unmixed with pain is of Sattvika nature. The Rajasika types worship Yaksas and Raksasas. And the others, i.e., the Tamasika types, worship the departed ancestors and hosts of Bhutas. The faith born of Rajas brings about limited joy mixed with pain, while the faith born of Tamas gives rise to extremely limited joy which verges almost on pain.

Therefore, there is difference in fruits according to the Gunas regarding sacrifices etc., which are enjoined in the Sastras and associated with faith. However, no happiness whatsoever will result from penances, sacrifices etc., not enjoined in the Sastras and therefore antagonistic to My ?ndment. On the contrary, calamity results from them. Sri Krsna proceeds to explain this more fully.