Confirm (one) in (something) verb phrase
To perform a religious sacrament, ritual or rite that ties one more closely to one's religion
The bishop is confirming the children in the church.
He was confirmed in the church yesterday.
The verb “confirm" should be conjugated according to its tense.
The verb "confirm" dates from 1250 to 1300; (Latin "confirmār" to strengthen), "confirm" also replaced Middle English "confermen".
Meaning absolutely certain or without a doubt
I am as sure as God made little green apples that Peter's the one for you, you two make a beautiful couple.