Text 16

aham kratur aham yajnah
svadhaham aham ausadham
mantro ’ham aham evajyam
aham agnir aham hutam

Translation

But it is I who am the ritual, I the sacrifice, the offering to the ancestors, the healing herb, the transcendental chant. I am the butter and the fire and the offering. 

Commentary by Srila Prabhupada 

The Vedic sacrifice known as jyotistoma is also Krishna, and He is also the maha-yajna mentioned in the smriti. The oblations offered to the Pitrloka or the sacrifice performed to please the Pitrloka, considered as a kind of drug in the form of clarified butter, is also Krishna. The mantras chanted in this connection are also Krishna. And many other commodities made with milk products for offering in the sacrifices are also Krishna. The fire is also Krishna because fire is one of the five material elements and is therefore claimed as the separated energy of Krishna. In other words, the Vedic sacrifices recommended in the karma-kanda division of the Vedas are in total also Krishna. Or, in other words, those who are engaged in rendering devotional service unto Krishna are to be understood to have performed all the sacrifices recommended in the Vedas.

Commentary by Sri Visvanatha Cakravarti Thakur

Please see text 19 for Sri Visvanatha Cakravarti Thakur's combined commentary to texts 16, 17, 18 and 19.