Indian man: Srila Prabhupadaji, regarding karma: one does his job every day, and if he spends some time in the evening in chanting Lord Krsna, do you approve this?

Prabhupada: Oh, yes. Why not? Svalpam apy asya dharmasya trayate mahato bhayat [Bg. 2.40]. If you think of Krsna once, that will not go in vain. That is recorded. Svalpam apy asya dharmasya trayate mahato bhayat. Just like Ajamila. At the last stage of his life he chanted "Narayana" and became liberated. So something is, about Krsna, is very good. And you'll get chance to increase. If you believe that by chanting Hare Krsna you'll be liberated, then why fifteen minutes? Why not fifteen hours? What is the loss there? If you chant Hare Krsna, Hare Krsna, what is the loss? Is there any loss? Then? Why fifteen minutes? Chant, kirtaniyah sada harih [Cc. Adi 17.31], as long as you can. Now chant Hare Krsna.

From Srila Prabhupada's lecture on Bhagavad-gita 7.3 — October 29, 1975, Nairobi