Where did you “gather” this from? I’ve never heard of that.
I would say it’s not advisable to mimic the gestures proper to the clergy. It’s certainly not allowed in the liturgy, as per the GIRM, and I think that “blessing” things after the manner of a cleric is problematic. I knew of a few younger seminarians who would “practice” blessing things at meals, only to be gently corrected by the more senior men, since that was something proper to the ordained.
-Fr ACEGC
Hello Father:
I read this on a Catholic Answers tract:
START
In the name of the Father
and of the Son
and of the Holy Spirit. Amen.
What is the sign of the cross, and why do we make it?
Not all prayers are made with words. Prayers may also be made by gestures. Christians, like followers of all other religions, practically always pray by the position of the body—say, kneeling or standing—and of the arms and hands—for example, praying with hands outstretched or folded in front. Because we are both body and soul (a human being is not one or the other; a human being is both! We are not angels or simply spirits), we pray with both.
Now, all religions have gestures that express a devout attitude before the divine or heavenly beings they invoke, but the gesture that is most expressly Christian, and used only by Christians, is the sign of the cross. By making it, we profess the central truths of our faith: that
God became one of us, with a human body and soul; that he died on the cross to save us; and that our own bodies and souls share in the same power of the Savior whereby we are freed from sin and death and brought to the resurrection and the life of heaven.
From the earliest times Christians have made the sign of the cross.
St. Basil the Great tells us that the apostles themselves taught the sign of the cross. This is shown by the fact that the earliest mentions of the sign of the cross speak of it as an already established custom and simply encourage the faithful to make it correctly.
The sign of the cross was made simply with the fingers (the index or the thumb) on the forehead or lips or breast (as Latin-rite Catholics do at the beginning of the Gospel lesson) or with the whole hand over the torso. There are slight differences in how it is made between the various rites of the Church, but they are all legitimate.
Those who are in holy orders bless by making the sign of the cross in the air toward the persons or things to be blessed, but layfolk bless others only by using their finger, usually the thumb. This “lay blessing” is common in Catholic cultures, made by parents on their children before bed or before going out or on a trip. It would be great if this custom could be revived.
…
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I read the part in bold as being that laypeople could ask God to bless people/things by using their thumb.
I have probably misinterpreted it. I stand corrected.
Here is link to the tract:
Sign of the Cross | Catholic Answers.
Sincerely Yours in Christ.