What does God-realisation really mean?
God-realisation, or siddhi means Self-discovery in the highest sense of the term. One consciously realises his oneness with God. As long as the seeker remains in ignorance, he will feel that God is somebody else who has infinite Power, while he, the seeker, is the feeblest person on earth. But the moment he realises God, he comes to know that he and God are absolutely one in both the inner and the outer life. God-realisation means one's identification with one's absolute highest Self. When one can identify with one's highest Self and remain in that consciousness forever, when one can reveal and manifest it at one's own command, that is God-realisation.
Now, you have studied books on God, and people have told you that God is in everybody. But you have not realised God in your conscious life. For you this is all mental speculation. But when one is God-realised, one consciously knows what God is, what He looks like, what He wills. When one achieves Self-realisation, one remains in God's Consciousness and speaks to God face to face. He sees God both in the finite and in the infinite; he sees God as both personal and impersonal. And in his case, this is not mental hallucination or imagination; it is direct reality. This reality is more authentic than my seeing you right here in front of me. When one speaks to a human being, there is always a veil of ignorance: darkness, imperfection, misunderstanding. But between God and the inner being of one who has realised Him, there can be no ignorance, no veil. So at that time one can speak to God more clearly, more convincingly, more openly than to a human being.
As ordinary human beings, we feel that infinite Peace, infinite Light, infinite Bliss and infinite divine Power are all sheer imagination. We are victims to doubt, fear and negative forces which we feel are quite normal and natural. We cannot love anything purely, not even ourselves. We are in the finite, quarrelling and fighting, and there is no such thing as Peace or Light or Bliss in us. But those who practise meditation go deep within and see that there is real Peace, Light and Bliss. They get boundless inner strength and see that doubt and fear can be challenged and conquered. When we achieve God-realisation, our inner existence is flooded with Peace, Poise, Equanimity and Light.
From "Samadhi and Siddhi, the summits of God-Life" by Sri Chinmoy