“The life of God—precisely because God is triune—does not belong God alone. God who dwells in inaccessible light and eternal glory comes to us in the face of Christ and the activity of the Holy Spirit. Because of God’s outreach to the creature, God is said to be essentially relational, alive as passionate love. Divine life is therefore also our life. The heart of the Christian life is to be united with the God of Jesus Christ by means of communion with one another.
The doctrine of the Trinity is ultimately therefore a teaching not about the abstract nature of God, nor about God in isolation from everything other than God, but a teaching about God’s life with us and our life with each other.”
Catherine Mawry LaCungna, God for Us: The Trinity and Christian Life