What is the metaphysical realm in the poem, Ode: Intimations of Immortality From Recollections of Early Childhood?

The unspecified metaphysical realm is briefly referenced in the fifth stanza of the poem. This metaphysical realm is described as the place where the soul resides before a person is born into the physical world. The speaker claims it is a faraway place, and closely associates it with God, saying “we come/from God, who is our home” (65-66).