Bhagavad Gita, Chapter 18, Verse 5

The work of Yajna, gift and austerity should not be relinquished, but it should indeed be performed; for Yajna, gift and austerity are purifying to the wise.

Even those already wise are named here as still needing these real, ongoing practices.

Krishna doesn't treat sacrifice and charity as beginner-level activities to be outgrown. Real purification, he says, keeps working even on those who've already advanced.