Who Invented the Trinity: One and Three? (Grades 7–12)

Where did the idea of the Trinity come from?

Did the Council of Nicaea invent it? Why did Christians spend centuries arguing over just one letter in a Greek word? And what does any of this have to do with faith today?

This workbook invites students to explore one of Christianity's most important—and most misunderstood—teachings through history, Scripture, language, and thoughtful discussion.

Rather than asking learners to simply memorize doctrine, this resource follows the questions early Christians wrestled with as they tried to describe their experience of God as Father, Son, and Holy Spirit. Along the way, students discover how Christian beliefs developed, why different viewpoints emerged, and why these conversations continue nearly 2,000 years later. 

Inside you'll find:

• The story behind the Trinity
• What Christians mean by "God"
• The Messiah and the identity of Jesus
• Early Christian debates about the Trinity
• Theophilus of Antioch and the first use of the word Trinity
• Arius, Athanasius, and the Council of Nicaea
• The Nicene Creed
• Homoousios vs. Homoiousios explained
• The legend of St. Nicholas and Arius
• A Trinity timeline
• A hands-on Trinity pyramid activity
• Word search and crossword puzzle
• Discussion and reflection questions
• Student glossary
• Parent and teacher notes

Resource Details

• PDF download
• 26 printable pages
• Grades 7–12
• Suitable for homeschool, Christian schools, confirmation classes, youth groups, Bible studies, and adult education

Part of the Black Series: What We Believe from Our Common Table, helping learners explore Christian history, theology, and faith through curiosity, historical evidence, and respectful conversation.

Looking for more?

Explore other Our Common Table resources, including:

• 🟡 Bible Literacy – understanding how the Bible was written, organized, and read
• 🟣 Women of Scripture – exploring biblical women through history and archaeology
• ⚪ Christian Seasons – the history and traditions behind the Christian calendar