Jiva (being) is nothing but God (the Lord of all beings - Pasupathi) himself who is acting the role of egoism. That Jiva (being) is the Pasu. Pasupathi is he who knows everything, who does the five jobs like creation, and who is the Lord of all beings. Pasu (in common parlance) are those animals which eat grass, which do not have viveka (knowledge to differentiate), which are driven by others, which are made to work in jobs like agriculture, and which undergo lot of sufferings. Similar to the owner of such animals is the God Pasupathi who rules over all beings.