Your link in FamilySearch can only be accessed at a Family History Center of FamilySearch Affiliate Library.

However, the Italian government's Antenati portal houses many of the Italian civil records; they have an agreement with FamilySearch, who does the scanning. Under the agreement, scans of documents held by the state archives are not made freely available on FamilySearch; instead they are published on the Antenati site.

In this case the document you linked to is available on Antenati (the folder name and image number are the same). Odd that they have marriage records stuck in a births folder, but it happens.

"https://www.antenati.san.beniculturali.it/ark:/12657/an_ua61894/02PAQQL" is the link.

I could swear I have seen this record before? BTW there is a second (more readable) copy located in this same folder at image 126. Anwyay:

7 Mar 1813

Groom: Tommaso di Muccio, age 23, farmer, living on strada San Giovanni in Vairano, son of deceased Francesco and deceased(?) Angela Vallante, both died in Vairano; since he has no grandparents his aunt Mariangela di Muccio, age 50, farmer, living with her nephew, has given her consent.

Bride: Mariangela Moliterno, age 28, farmer, living on strada San Giovanni, daughter of deceased Francesco Moliterno and deceased(?) Isabella Iasimone, both died in Vairano, since she has no grandparents her aunt Antonia di Muccio presented a consent made by a family council.