Only in your twisted mind would that conclusion be drawn. There is no indication he thought the unwed sex was worse than rape.
"Twin Falls County Prosecutor Grant Loebs called the judge’s move a “fairly routine sentencing on a fairly routine case.” Loebs said probation is intended to restrict certain behaviors related to the crime. For instance, for someone convicted and sentenced for drunken driving, the terms of probation may stipulate no drugs or alcohol. In the same way, a sex offender may be required to report to his probation officer before he goes on a date.
In Herrera’s case, the judge said that if he is indeed given probation instead of prison, the terms of that agreement will include no sex outside of marriage.
“We don’t just put sex offenders on probation and then not care what they do,” Loebs told The Washington Post. He emphasized that probation is an agreement and, assuming that offer is made, Herrera can reject it. But he might not get an offer at all if he turns this one down, Loebs said."
If you want to argue he should have been punished more severely for the rape, I can agree with you. But there is absolutely no indication that this has anything to do any sort of religious belief that premarital sex is worse than rape. The judge is simply imposing a behavioral limitation in the course of negotiating a routine plea agreement.