It doesn't matter what kind of action you are engaged in. You can be united with God through any action provided that, performing it, you give up all desire for its result.
You don't want anything of God but still you love Him. That is pure bhakti, love of God with no motive behind it. Prahlada had it. He sought neither kingdom nor riches; he sought Hari alone
A man may be united with God either through action or through inwardness of thought, but he can know everything through bhakti. Through bhakti one spontaneously experiences kumbhaka. The nerve currents and breathing calm down when the mind is concentrated. Again, the mind is concentrated when the nerve currents and breathing calm down. Then the buddhi, the discriminating power, becomes steady. The man who achieves this state is not himself aware of it.
One can attain everything through bhakti yoga. I wept before the Mother and prayed, 'O Mother, please tell me, please reveal to me, what the yogis have realized through yoga and the jnanis through discrimination.' And the Mother has revealed everything to me. She reveals everything if the devotee cries to Her with a yearning heart. She has shown me everything that is in the Vedas, the Vedānta, the Puranas, and the Tantra.