God's essence is distinct from His energies in the same way the sun is distinct from its rays. God's essence is incomprehensible to us, just as the surface of the sun is hostile to our personal exploration. The heat of the sun would burn us up. It is completely unapproachable. Likewise, God's essence is unapproachable by finite creatures. We can, however, experience God through His energies, just as we experience the sun through its light, heat, impact on weather, etc. We experience God through sensing His presence in prayer and worship, inspiration, through the enlightening experiences given by the Holy Spirit, miracles, and through such things as love, beauty, and truth. These experiences of God are a real way of knowing Him, but don't change what we are nor what God is. It can change how we live and who we are in relationship to God. In other words, this way of knowing God can bring about a positional and consciousness change, but we never become what God is by virtue of these experiences. We do, however, have the opportunity to become a child of God. These energies are God immanent, while his ousia (essence) is God in His transcendence. It is important to note here that there isn't a division in God, just a limitation on our part as finite beings to know God in His essence. God in His ousia is the one that subsists by Himself and which doesn't take His being from another. Essentially this is God as God is, not as He is experienced by the finite through His energies or activities in the material world. God's energies, like His essence, are uncreated, as they proceed from His essence. His existence, essence, and energies are all uncreated, interconnected, and eternal.
In Christ we know that, "For in him the whole fullness of deity dwells bodily." (Colossians 2:9), so the ousia was clearly present, yet He wasn't directly experienced in His essence, but through His energies-His activities; words, deeds, miracles, birth, death, resurrection, love, rebuke, etc. In Christ we have the closest finite humanity can come to a direct experience of God's essence.