A Krishna Devotee Does Not Have

Obligations for Vedic Rituals

A Devotee of Krishna Is Not Obligated to Execute Any Vedic Rituals

Because a devotee fully engages in the supreme service of the Lord, he automatically fulfills all other obligations and does not have to execute all the details of Vedic rituals.
As the Srimad-Bhagavatam (11.5.41) says,

devarsi-bhutatpta-nrnam pitrnam
na kinkaro nayam rni ca rajan
sarvatmana yah saranam saranyam
gato mukundam parihrtya kartam

"Every human being born in this world is immediately indebted to the demigods, the great sages, ordinary living entities, the family, society, and so on. But a person who surrenders unto the lotus feet of the Lord (Krishna) and engages fully in His service is no longer indebted to anyone. In other words, he had no obligations to fulfil except executing devotional service."

Thus the activities of a devotee remain always pure and without any contamination of the material world.

- Srila Prabhupada in Purport to Narada-Bhakti-Sutra, Sutra 5