God “only hath immortality, dwelling in the light which no man can approach unto; whom no man hath seen, nor can see” (1 Tim 6:16). God reveals himself in part (Exod 33:20) and through his works (Rom 1:19–20). He is also seen in the person of Jesus Christ (John 14:9).
It does not imply that God can be likened to an unseen ghost that might be said to inhabit a haunted house. This cannot be, for any would-be ghost, however invisible, could only occupy one given moment in time. The invisible God, however, occupies all space at all times!