Noun
trinitarian formula (uncountable)
(religion, Christianity) The phrase "in the name of the Father, and of the Son, and of the Holy Spirit", or words to that form and effect, referring to the three persons of the Christian Trinity.
Trinitarian formula (uncountable)
Alternative letter-case form of trinitarian formula
Any supposed baptism not performed using the Trinitarian formula is considered invalid. Source: Internet
Current canonical law requires the Trinitarian formula and water for validity. Source: Internet
It was because of Eusebius that "On the whole, Constantine and his successors made life pretty miserable for Church leaders committed to the Nicene decision and its Trinitarian formula." Source: Internet