Father-of-two Mark Pearce made advances towards the girl, who was 14 or 15 at the time, when they were alone at the MPM Studio in Walsall and in his car.
The 42-year-old, who had twice before been convicted of sexual assaults on young people, was described as a 'persistent ' offender.
Wolverhampton Crown Court heard Pearce was pastor at The New Testament Church of God in Bilston, despite being on the sex offenders' list for his previous convictions in 1993 and 2002.
The new offences took place 12 years ago but were not reported until last year when the victim, who had since become a Christian and got married, saw him in a pulpit surrounded by young people.
Although she had forgiven him, she reported him to the police because she was worried he might assault other children.
Pearce, of Church Green, Stowlawn, Wolverhampton, was unanimously found guilty of three sexual assaults and a count of indecency against a child by a jury at the court.
He had denied all the offences.
Miss Samantha Powis, prosecuting, said the assaults bore a 'staggering similarity' to the previous convictions.
She said Pearce 'held himself up as a devout man of God' yet chose not to swear on the Bible to give evidence, instead making a non-religious affirmation.
Pearce denied touching the victim in any way, claiming his wife was always with him at the studio and that he did not have the use of a car in 2002 when he was alleged to have given her lifts.
He also thought she was 'about 16,' the court heard.
The court also heard how the victim was a talented singer whose mother paid for her to record an album at the Bath Street studio.
The offences involved Pearce touching her buttocks and breasts and also touching himself inappropriately in front of her.
Of the first occasion, the victim said: 'I didn't tell him no, I just froze, I didn't know what to do."
After that, she asked her mother or boyfriend to accompany her although did not tell them why.
She could not give exact dates but believed the offences had already taken place by the time she was 15.
The convictions in 1993 - five indecent assaults and a gross indecency with a child - occurred when Pearce was working as a teacher in a Wolverhampton school.
In December 2002 he was jailed for six indecent assaults, including one on a sick girl when he visited her in hospital.
Sentencing will take place next month.
Pearce, granted conditional bail, was warned he was facing prison again.