Advaita performs the deeds of Dvaita, assuming the names Sagun and Nirgun.

This couplet beautifully explains that even though reality is fundamentally non-dual, or 'Advaita', meaning everything is one, it still operates in the world of 'Dvaita', which is duality and diversity. It's like how a single ocean appears as many waves. Similarly, the ultimate reality, which is 'Nirgun' or without attributes, takes on 'Sagun' forms, meaning it manifests with qualities and names that we can perceive and interact with. So, 'Sagun' and 'Nirgun' are just different ways we understand or label the same singular truth. Ultimately, it all points to the idea that the one true essence works through and appears as the many forms we see around us.