It is important to build your understanding of the Trinity from the Scriptures, which are perfect, and not an external source, which is imperfect. Extra-biblical sources can be very helpful in explaining and understanding what the Bible teaches, but the foundation must be Scripture.

The belief in Triune God is a core foundational doctrine of the Christian faith. Triune, or Trinity, is a shorthand way of describing the God revealed in the pages of Scripture, who has revealed Himself as three persons (who) unified in one Being, Yahweh (what). The three distinct persons are the Father, the Son, and the Holy Spirit, with the Son proceeding from the Father, and the Holy Spirit proceeding from both the Father and the Son. Each is distinct in their relationship, but are uncreated, co-equal, co-eternal, full deity, acting with one will, and not confused. Each is the holy, all-knowing, all-powerful, all-present, sovereign, loving, and just Lord of glory, Yahweh.

Application of Doctrine

Let’s be frank here, this is not a lightweight or easy doctrine. We must recognize that there is manifold mystery to behold in the Trinity. It should not make us run away from it, but draw us in to worship. We look with awe and wonder at the depth, breadth, and beauty of the universe and its endless number of stars and galaxies. It stretches the mind beyond its limits and humbles us. How much more the Triune God who created it? Like David in Psalm 8, we should look in awe towards our Creator, and wonder: What is man? How and why does this immense and infinite God who defies categories and understanding, have regard for me? Why does He not just have regard, but also care for and love me?

How precious to me are your thoughts, O God! How vast is the sum of them! If I would count them, they are more than the sand. I awake, and I am still with you.
—Psalm 139:17-18 (ESV)

Such knowledge is too wonderful for me; it is high; I cannot attain it.
—Psalm 139:6 (ESV)

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