Trinitarian formula

Pronunciation of the trinitarian formula in Latin: "In nomine Patris et Filii et Spiritus Sancti, amen"

The "Shield of the Trinity" or "Scutum Fidei" diagram of traditional Western Christian symbolism

The Trinitarian formula is the phrase "in the name of the Father, and of the Son, and of the Holy Spirit" (Koinē Greek: εἰς τὸ ὄνομα τοῦ Πατρὸς καὶ τοῦ Υἱοῦ καὶ τοῦ Ἁγίου Πνεύματος, romanized: eis to ónoma toû Patros kai toû Huioû kai toû Hagíou Pneúmatos; Latin: in nomine Patris et Filii et Spiritus Sancti), or words to that form and effect, referring to the three persons of the Christian Trinity. It is often followed by an "amen".

The Trinitarian formula is used in baptism as well as in numerous prayers, rites, liturgies, and sacraments. One of its most common uses apart from baptism is when Roman Catholics, Eastern and Oriental Orthodox, Lutherans, Anglicans, Methodists, and others make the sign of the cross while reciting the formula.