That's not in Scripture, and it's not supported by Scripture.
You have criticized others for adding to Scripture, but that is exactly what you did here with the words in bold.
I see that a little differently.
A person would have to rightly divide the parable/prophecy in order to see if what I offered is supported by scripture.
He hides the gospel understanding from those who wonder and doubt.
Some like Gordon Fee destroy the intended use of parable. In his book "How To Read the Bible for All Its Worth" . He says parables are fiction, but good fiction is the best way to handle truth. and said telling a story is the point no need to hide anything, walk by sight.
True or false? Is there a spiritual understand hid in prophecy and we look to the unseen eternal and not that seen the temporal ? or the other way around?
How is searching out the meaning of a parable adding?
Not searching makes the teaching that we "walk by sight" .Is that what Jesus was saying to doubting Thomas ? Learn how to walk by sight? .It would seem he apposes that kind of ideology of wondering and not exercising faith. . .believing.
John 4:48 Then said Jesus unto him, Except ye see signs and (or as) wonders, ye will not believe.
What you offer seems to subtract from the witness (as it is written). As if Christ was trying to appose the teaching of faith .
Previous to the loving commandment of Christ's labor of love :
"be not faithless but believe" .Thomas doubted. . he simple fulfilled the law as a witness to the work that worked in Thomas. . That if Christ gives a person the power to believe, in their heart with their mouth they confirm the work of God working from within . ..(
John 20:28 And Thomas answered and said unto him, My Lord and my God.
The loving law. . .
Romans 10:9That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.
Wondering, doubting . . . .using ones own imagination is not working out the faith of Christ, that does work in us.
The parable remains a parable to those who refuse to do the good work of rightly dividing them .(no gospel message )
I say Thomas was moved by the Holy Spirit to confess the work of Christ, that gave Thomas power to believe, (
be not faithless, but believing. )
Romans 14:23 And he that doubteth is damned if he eat, because he eateth not of faith: for whatsoever is not of faith is sin
Is doubting sin? Or again was Jesus putting his seal of approval on doubt and wondering?
I would suggest. He did not say to Thomas open your eyes and put place your hand here why trust the unseen? ?