Very likely he is, yes. The Church teaches that for a sacrament to be valid there must be valid “matter,” “form,” and “intention.”
For the Eucharist, the matter is the wheat bread, the form is the words “This is my Body”, and the intention is the priest’s intention to confect the sacrament as the Church intends.
For confession, the matter is the priest
in persona Christi (in the person of Christ, by virtue of his ordination), the form is the words “I absolve you from your sins, in the name of the Father, and of the Son, and of the Holy Spirit,” and the intention is on the part of the penitent who comes to the sacrament with repentence and a firm conviction to keep from sinning.
The issue of “form” is the one most discussed in relation to the validity or invalidity of a sacrament… There have been many cases of invalid Masses because the priest changes some (seemingly small, at least to him) word during the consecration, thereby using an invalid form. In addition, there have been many cases where baptisms are deemed invalid due to improper form (in Australia, a recent high profile case was where a pastor was baptizing kids “in the name of the Creater, Redeemer and Sanctifier” – the bishop there declared all his baptisms invalid).
In light of all of this, it follows that the words used for the sacrament of penance are also of the utmost importance, for these words are also the form.
The Church has had a long history of discussion on what constitutes valid form for the sacrament of penance, much of that is detailed in the
Catholic Encyclopedia (but it is very dense reading… very complicated and using advanced theological/philosophical language).
I do not have any further citations for you, but I belive that since the Church has determined that the only formulation it can be
sure is valid is the “I absolve you from your sins, in the name of the Father, and of the Son, and of the Holy Spirit,” then any divergence (no matter how “slight” it seems) is questionable and is an offense to the integrity of the sacrament. I did check the Code of Canon Law quick and did not find an explicit description of the proper form for absolution, but I am sure it is in the rubrics for the rite of confession.
In any case, yes, I agree with the EWTN priest on this matter.
Any time I encounter a priest during confession who changes the words of absolution even slightly, I politely ask him to repeat it using the correct form…
+veritas+