Why Is It So?, episode 1 (1963) http://www.abc.net.au/science/features/whyisitso/, Australian ABC Television show
Context: Whatever work you undertake to do in your lifetime, it is very important that first you have a passion for it — you know, get excited about it — and second, that you have fun with it. That's important. Otherwise, you see, your work becomes nothing but an idle chore. Then, you hate the life you live.
“Whatever you do will be insignificant, but it is very important that you do it.”
The earliest attribution of this to Gandhi yet located is in a T-shirt advertisement in Mother Jones, Vol. 8, No. 5 (June 1983), p. 46
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Mahatma Gandhi 238
pre-eminent leader of Indian nationalism during British-rul… 1869–1948Related quotes

“Whatever you do willingly, you enjoy. Whatever you do unwillingly, you suffer.”

Quoted in Conversations with Willie (1978) by Robin Maugham

“Whatever you do, do it well.”
As quoted by Diogenes Laërtius, i. 77.

Psychomagic: The Transformative Power of Shamanic Psychotherapy (2010)
Context: I say: "What you give, you give to yourself; what you do not give, you give up." And this is to say that whatever you do in the world, you do to yourself; and whatever you do not give to the world, you lose. If I keep my knowledge, I lose it. (...) One receives knowledge and gives it. When you give knowledge, you enrich yourself. If you do not give love, you are detracting from yourself. If I begin to help people, if I begin to heal people, I begin to heal. Do you understand? To be a therapist, you have to be a patient. The first thing to do to heal yourself is to heal others. I have one more saying: "I do not want anything for myself that I do not want for others".

“If you bungle raising your children I don't think whatever else you do well matters very much.”
Interview with NBC News Correspondent Sander Vanocur (1 October 1960) https://web.archive.org/web/20140127091759/http://www.jfklink.com/speeches/joint/joint011060_nbctv03.html

Television interview ("On clarity and exact thinking" - available on youtube)
1960s