Is God's presence really here in my heart?

Suppose that is your belief, but now you come to Satsang and a mad person is telling you that actually your idea of your life and of this world is a little bit limited and reality is much bigger than that and there is the reality of God and His presence sits in your heart in the form of the Atma. So you heard these foolish words, now what options do you have, you can say it's all but suppose that you say that you admit, like I admit it at one point in my life that I really don't know, is this true, is God the one God who is the God of this universe and every universe, is His presence really here in my heart?