That Brahmana who becomes the priest at a Shraddha forins himself by that deed, the Pitri of the person performing ine Shraddha. Hence he should abstain that day from sexual intercourse with even his own wife.
ऋत्विग्यो यजमानस्य पितृत्वमनुगच्छति॥ हव्यवाहे तु यः तस्मिन्नहनि मन्यन्ते परिहार्ये हि मैथुनम्।