Belief, Religion, Spirituality and Gita
Do you need to believe in anything to benefit from the teachings of the Bhagavad Gita?
How to study the Bhagavad Gita
The ultimate goal of the Bhagavad Gita is for the person to realize his inner divinity (Atman-Jnana, Self-knowledge) to unite with the Absolute, whatever it is called: God, Parabrahman, Sat-Chit-Ananda or Allah. That is, achieve self-knowledge.
Spirituality, religion and the Bhagavad Gita
For this, Sri Krishna taught different Paths of Yoga to achieve it:
But no one can resort exclusively to one of them. For example, Karma or Jnana Yoga cannot be followed without Jnana Yoga.
The Bhagavad Gita furthermore, and Sri Ramakrishna in particular, affirm that any path (yoga, religion, philosophy) that the human being follows will equally lead him to the Higher Absolute Reality. That is to say, it does not matter whether one is Christian, Muslim or Hindu, in the end the same objective is reached.
The philosophical school followed by the Bhagavad Gita Institute & Pedro Nonell is Advaita Vedanta (non-dual), which encompasses all religions and beliefs, even dualistic systems (Dvaita).
From a more technical point of view, Chapter 1 of the Bhagavad Gita (The Yoga of Arjuna’s Despondency) is accessible to everyone, regardless of what one believes. The concept of the Atman, the infinite Soul, is present in almost all religions, even agnostics believe it, but doubts arise whether atheists would accept the concepts of Chapter 2 (Sankhya Yoga), on which the entire Bhagavad Gita is based.
The great advantage of Karma Yoga is that it is applicable to all humanity, whether one is Buddhist, Agnostic, Christian or Jain. And that is the great contribution of Karma Yoga. And Vivekananda demonstrated it well in his essays on Karma Yoga.
Obviously, the other paths, especially Bhakti Yoga, you have to believe in something, otherwise it is difficult to imagine what to worship. Be that as it may, Bhakti Yoga is the path of Christianity, Islam, the Bhakti path of Hinduism (Dvaita), etc.
Jnana Yoga really is a path designed above all for those who mainly follow Vedanta, but let us remember that Vedanta encompasses all religions, in fact, Christianity says something similar: “The Kingdom of God is within you.” (Leo Tolstoy) which is so reminiscent of the “All is One” of Vedanta.
However, our big doubt is with atheists: can they benefit from the Bhagavad Gita? Perhaps the following reflection by Sri Ramakrishna will help you focus your study of the Bhagavad Gita:
That is, we do not ask that the seeker “go to mass every day”, nor that he follow this or that Spiritual path or religion, simply that he believe in something Superior that “follows the path of good”, and that he does not believe that “man It is the measure of all things” (Protagoras). Let it be clear that above all we respect any belief or non-belief.
¿Hay que creer in algo para beneficiarse of the enseñanzas del Gita? 
Crença, religião and Bhagavad-Gita.
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