Because his (King Saudasa's) duty is to rule the kingdom to maintain brahminical culture, he never desires to kill a brahmana

Expressions researched:
"Because his duty is to rule the kingdom to maintain brahminical culture, he never desires to kill a brāhmaṇa"

Srimad-Bhagavatam

SB Canto 9

The word rājarṣi refers to a king who behaves like a ṛṣi, or sage. Such a king is also called naradeva because he is considered a representative of the Supreme Lord. Because his duty is to rule the kingdom to maintain brahminical culture, he never desires to kill a brāhmaṇa. Generally, a brāhmaṇa, woman, child, old man or cow is never regarded as punishable. Thus the wife of the brāhmaṇa requested the King to refrain from this sinful act.

SB 9.9.30, Translation and Purport

My lord, you are completely aware of the religious principles. As a son never deserves to be killed by his father, here is a brāhmaṇa who should be protected by the king, and never killed. How does he deserve to be killed by a rājarṣi like you?

The word rājarṣi refers to a king who behaves like a ṛṣi, or sage. Such a king is also called naradeva because he is considered a representative of the Supreme Lord. Because his duty is to rule the kingdom to maintain brahminical culture, he never desires to kill a brāhmaṇa. Generally, a brāhmaṇa, woman, child, old man or cow is never regarded as punishable. Thus the wife of the brāhmaṇa requested the King to refrain from this sinful act.