It is said that among all the devotees of the Personality of Godhead, Lord Śiva is the greatest. Thus the remnants of foodstuff left by him are accepted by other devotees as mahā-prasāda, or great spiritual foodstuff. The remnants of foodstuff offered to Lord Kṛṣṇa are called prasāda, but when the same prasāda is eaten by a great devotee like Lord Śiva, it is called mahā-prasāda. Lord Śiva is so great that he does not care for the material prosperity for which every one of us is so eager. Pārvatī, who is the powerful material nature personified, is under his full control as his wife, yet he does not use her even to build a residential house. He prefers to remain without shelter, and his great wife also agrees to live with him humbly. People in general worship goddess Durgā, the wife of Lord Śiva, for material prosperity, but Lord Śiva engages her in his service without material desire. He simply advises his great wife that of all kinds of worship, the worship of Viṣṇu is the highest, and greater than that is the worship of a great devotee or anything in relation with Viṣṇu.