"of unpitying self-denial"

Self-denial is the sacrifice of one's own desires or interests, and "unpitying self-denial" would sacrifice without any repentance or sense of misfortune at having to renounce worldly pleasures. Self-denial can take the form of asceticism or abstinence. In the context of Buddhism, self-denial can also be understood as no-self or anattā.

In the early texts, Buddha preached that all things perceived by the senses (including the mental sense) are not really "I" or "mine," and not worthy of one’s attention.

The Dhammapada 367 states, "He who has no thought of "I" and "mine" whatever towards his mind and body, he who grieves not for that which he has not, he is, indeed, called a bhikkhu (asectic)."

From the Christian perspective, true self-denial concedes self-interest to the divine interest.

As Richard Baxter, a puritan, says, "Wherever the interest of carnal self is stronger and more predominant habitually than the interest of God, of Christ, of everlasting life, there is no true self-denial or saving grace; but where God's interest is strongest, there self-denial is sincere."