Section — Wouters, Manual of Moral Theology
Section II. On the Form
The legitimate form is:
I. For the Latin Church: "I sign you with the sign of the cross and confirm you with the chrism of salvation, in the name of the Father and of the Son and of the Holy Spirit." Probably these suffice for the essence: I sign and confirm you; or, I confirm you with the chrism of salvation; since these alone are found equivalently in the form of the Greeks. Nevertheless it is also probable that all things in the form are essential; this depends on the question what the direct power of the Church is concerning the value of the sacraments (cf. St. Thomas, III, q. 72, a. 4; St. Alphonsus, VI, 167, 168).
II. For the Greek Church: "The seal of the gift of the Holy Spirit." Yet it is disputed whether the invocation of the Most Holy Trinity also, which in the Greek Euchologia is premised to chrismation, pertains to the essence. Several of those who judge that in the Latin form all things, even the expression of the Most Holy Trinity, are essential affirm this; and they are bound to affirm it unless they admit that Christ did not determine the form of Confirmation in a fixed specific form.