1 Corinthians 2:10-14

But it was to us that God made known his secret by means of his Spirit. The Spirit searches everything, even the hidden depths of God's purposes. It is only the spirit within people that knows all about them; in the same way, only God's Spirit knows all about God. We have not received this world's spirit; instead, we have received the Spirit sent by God, so that we may know all that God has given us. So then, we do not speak in words taught by human wisdom, but in words taught by the Spirit, as we explain spiritual truths to those who have the Spirit. Whoever does not have the Spirit cannot receive the gifts that come from God's Spirit. Such people really do not understand them; they are nonsense to them, because their value can be judged only on a spiritual basis.