Even these actions should be performed leaving delusional clinging and the desire for gain. This is my well-considered view, O Partha.
Krishna emphatically states that like all secular acts in life, the divine ones such as yajna, dana and tapas also are to be performed without delusional clinging (sanga) towards their results. Once this is ensured, the difference between secular and divine acts, inasmuch as their spiritual effects are concerned, totally ceases, and the whole life becomes pure and divine (3.19).
Krishna’s primary instruction is to avoid sanga in all thoughts and actions. Once this is done, all activities equally become divine, with no need to specially take up yajna, daana and tapas. In fact, sannyasa is a result of such comprehensive spiritual enrichment and sublimation (4.23).
One, who has left his clinging and does everything with ease, poise and delight, will need no further religious or spiritual merit for his inner enrichment and fulfilment. This itself makes life pure, sublime and lofty. The process is inward and the result is wholesome.