The Vedas and Shastras say that there is no means of attaining God. God is beyond the reach of limited and material senses, mind and intellect, and these are the only three criteria through which a human attains knowledge. Material mind and intellect fail to comprehend even material phenomena, what to speak of God!
Moreover, God possesses innumerable mutual contradictions within Him. He is bigger than the biggest, yet smaller than the smallest. He is without name and form, but also with name and form. He is farther than the farthest, yet nearer than the nearest. God does not take birth, yet takes birth innumerable times. For all these reasons and more, it is impossible to know God with material senses, mind and intellect.
Finding out that God cannot be known, is very disappointing. But the Vedas instill hope in our hearts by clarifying that though He cannot be known through self-effort, yet He can be known through Divine Grace.
When God bestows grace, the material senses, mind and intellect become divine, and then they can see, hear, taste, touch, smell and know God.