God (Brahman) alone is real; the world is illusory.
God alone is real, the Eternal Substance; all else is unreal, that is, impermanent.
When asked about a story concerning a farmer, Ramakrishna said:
The farmer was a Jnani; therefore he realized that the waking state is as unreal as the dream state.
There is only one eternal substance, and that is God (Atman - God's spirit in man).
For the Bhakta, God assumes forms. But for the Jnani, God is formless.
Thus God has form and, again, is formless. Because the mind cannot be fixed, all of a sudden, on the formless aspect of God, it is wise to think of God with form during the primary stages.
That which is Brahman is also Kali, the Mother of Primal Energy.
It is God who manifests Himself as the atheist and the believer; the good and the bad; the real and the unreal; that it is He who is present in waking and in sleep.
And... He is beyond all these.