Invocation of the trinity

In Paul Turner's Blog by Paul Turner

Q: I read your blog about invalid baptisms. I know a priest who always ends the invocation of the trinity with “amen”. This doesn’t  make it invalid does it?

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A: I can’t imagine that an “amen” would make it invalid because the formula is complete by then. But it’s not a good practice. This latest directive from the Vatican should impress upon all of us not to play with the formulas of any of the sacraments.