It's been a long time, Forfarian. I hope things a well. I have found a record of thier marriage. Would there be a marriage certificate and if so would the parents names be on that?
If it's a marriage in Scotland after 1855, then yes, there would be a certificate and their parents' names would be on it, including mothers' maiden surnames.
If it's a church record before 1855, there is no certificate and it is not likely that the record contains any information about the parents.
If it's in England, Ireland or Wales it would have the fathers' names but not the mothers' - not even their given names, let alone their surnames.
So assuming that the marriage you have found is the one of John Anderson to Ann Erskine in Forfar in 1840, it probably won't tell you who their parents were.
Ann Erskine or Anderson died in Forfar in 1893 aged 73, mother's maiden surname Watt (that last detail has been added to the index by SP since I previously gave you the pointer to that death). Ann Erskine, one of five recorded children of Andrew Erskine and Catherine Watt, was baptised in Forfar on 27 July 1820. Her death certificate should confirm the names of her parents, and tell you whether or not John survived her, which will narrow down the search for his death.
John and Ann are both in the 1891 census in Forfar: John aged 76, born Rescobie, and Ann, 71, born Forfar.
There is a baptism of John Anderson in Rescobie in 1815, one of two recorded children of James Anderson and Elizabeth Dick. John Anderson, mother's maiden name Dick, died in Edinburgh in 1895 aged 79.
The other child of James Anderson and Elizabeth Dick was Susan, baptised in Rescobie in 1813. Susan Anderson or Gale died in Edinburgh in 1882 aged 69. Susan Anderson married James Gale in Dundee in 1851.