It
can be understood by reading the Hindu Scriptures that each of the God/Devas represent/have an aspect/energy of the Supreme Soul which is
called PARAM-ATMA, So in essence Hindu texts describes a complete DIVINE SYSTEM that
operates under the DIVINE POWER OF THE SUPREME BEING. Infact Lord
Krishana states himself that its only a small miniscule part of him who
creates, controls and destroy this universe.
In Bhagwata Geeta , Krishna is shown as The Supreme GodHead of PARAMATMA (the supreme soul). In Chapter 10, Lord Krishna states, He is everything, all deities belong to him, all cause belong to him, all emotions belong to him, He is time who creates and destroys all worlds, He is THE ONE IN ALL, All Prayers belong to
him,. All who worship their deity with pure devotion and love, and
adapts to Dharma, infact are worshipping the Supreme figure of him
only.
Full chapter is is available for reading in here : Sri Krishna- The Supreme Personality of Godhead
Moreover heavy importance is given to know him rather than believe him by following the path of Spirituality and Dharma. That's the only way the true reality of GOD can be found. Belief is just the first step stone of spirituality.
In-fact, This is the specialty of Hinduism that it lets multiple perspectives of the God to coexist on a single platform making it highly absorptive and adaptive culture.