Just as the unknowing act, O Bharata, attached to their actions, so should the knowing act, but free of attachment, wishing to hold the world together.
Explanation
Krishna is teaching Arjuna about action (karma), and has just said he himself keeps acting so the world does not fall apart. Here he says the wise person should be as active as the unwise, who work because they are attached (saṅga) to results, but without that attachment. The aim is lokasaṅgraha, which means holding the world together or guiding people by example.