Hi All,
Familysearch Beta has this possible Christening;
John SEALY, 17 April 1785, South Brent, Somerset, England
Parents JOHN and ANN
Now with regards to the Marriage you have in 1810 John was a Widower so there is a previous marriage to find;
From FreeREG;
John SEALEY, Widower
Susannah MANNING
21 May 1810, All Saints, Norton Fitzwarren, Somerset