Trinity Ceiling Mural in Church of Waidegg (Kirchbach, Austria) - Public Domain Catholic Painting

The Christian theology of the Trinity states that there is one God who exists in three coequal, coeternal, consubstantial divine beings: God the Father, God the Son, and God the Holy Spirit, who are three different individuals sharing one homoousion. "It is the Father who begets, the Son who is born, and the Holy Spirit who brings about," proclaimed the Fourth Lateran Council. The three individuals define who God is in this sense, whereas the one essence describes what God is.