I understand your logic, but it's unnecessary... This thread is not just about the non believing Jews questioning Jesus' illegitimacy it is specifically about verse 41. So lets get some context for what is about to transpire.
let's take this one at a time.
Jason has made it clear that he believes that when the Pharisees said in verse 19 "where is your father?" that they were beginning their snide remarks regarding His illegitimate birth. Here is the problem with that.
It's like a musical piece being played back and forth in rhythm between the spiritual and the physical.
Verse 15 - Jesus says the Pharisees judge according to the flesh (
Physical)
Verse 16 - Jesus says He judges with the Father (
Spiritual)
Verse 17 - The Law of the testimony (Scripture) of two people is valid (
Spiritual)
Verse 18 - Jesus and the Father both testify (
Spiritual)
Verse 19a - Pharisees said, "Where is your Father?" (
Physical)
Verse 19b - Jesus says they do not know him or the Father (
Spiritual)
Verse 21 - Jesus said
He is going away & they could not follow; And they would die in their sins (
Spiritual)
Verse 22 - Pharisees mocked Jesus' words as if he said He would kill himself (
Physical)
Verse 23a - Jesus said, the Pharisee are from beneath and of this world (
Physical) (
Bad Spiritual)
Verse 23b - Jesus said, He was from above and not of this world (
Spiritual)
Verse 24 - Jesus said they will die in their sins if they do not believe who He was (
Spiritual)
Verse 26 - Jesus says He speaks to the world those things that the Father told Him to say (
Spiritual)
Verse 27 - The Pharisees did not understand that Jesus spoke of God the Father (
Physical)
Verse 28 - Jesus says when they have lifted up the Son of Man they will know (
Spiritual)
Verse 29 - Jesus says the Father is with Him (
Spiritual)
Verse 30 - Many believed (
Spiritual)
Verse 31 - Jesus said to those Jews which believed to continue in His Word (
Spiritual)
Verse 32 - Jesus said you shall know the truth and it shall set you free (
Spiritual)
Verse 33 - Pharisees said they are of Abraham's seed and are not in bondage to any man (
Physical)
Verse 34 - Jesus said whoseover commits sin is the servant of sin (
Spiritual)
Verse 35 - He said
A bondservant does not remain in the house forever but a son remains forever (
Spiritual)
Verse 36 - He said if the Son makes you free you are free indeed (
Spiritual)
Verse 37a - Jesus said that He knows they are Abraham's offspring (
Physical)
Verse 37b - He also says that they seek to kill Him because His Word finds no place in them (
Spiritual)
Verse 38a - Jesus speaks that which He has seen with the Father (
Spiritual)
Verse 38b - He also says
They do which they have seen (
Physical) of their father (the devil) (
Bad Spiritual)
Verse 39a - Pharisees said Abraham is their father (
Physical)
Verse 39b - Jesus replied, if Abraham was their father, they would do his works (
Spiritual)
Verse 40 - Jesus said they seek to kill Him (
Physical) who told them a truth from God (
Spiritual)
Verse 41a - Jesus said they do the deeds (
Physical) of their father (devil) (
Bad Spiritual)
Verse 41b - Pharisees replied, "We be not born of fornication" (
Physical)
Verse 41c - Pharisees continue to say, "We have one Father, even God" (
Self Deceived Spiritually)
Verse 42 - Jesus said if God was their Father, they would love Him (
Spiritual)
Verse 43a - Jesus said,
"Why do ye not understand my speech?" (i.e. their lack of understanding) (
Physical)
Verse 43b - Jesus tells it is because they do not hear His Word (For hearing His word is
Spiritual)