Hi Kathryn,
had a scout round the baptism's & burials for Capel & Dorking at St. Martins the Parish church. No MARTIN Bax mentioned for Capel or Dorking. No THOMAS mentioned of the dob you gave in either parish, so looks like that might be in the Quaker records. That was the bad news. The good news is that I have what appears to be baptism's of possible children of Thomas & Sarah, all Dorking St. Martins
October 7 1827, Thomas son to Thomas & sarah Bax of PIXOM Lane. Just 5 months after the marriage
November 23 1828, Sarah daughter to Thomas & Sarah Bax of Back Lane.
August 29 1830, Mary daughter to Thomas & Sarah Bax of Back Lane.
January 6 1833, Elizabeth daughter to Thomas & Sarah Bax of Back Lane.
April 12 1835, Jane daughter to Thomas & Sarah Bax of Westcott.
February 26 1837, Rebecca daughter to Thomas & Sarah Bax of Westcott.
Now I don't know if Thomas & sarah of Back Lane & Westcott are one & the same. You need to look for marriages to establish that. At around the same time in Dorking were Edward & Ann Bax, married before Thomas & Sarah as they have a son, William in 1822 and they are from Pixom Lane, so my guess is that he is a brother to Thomas.
If Thomas's parents were Quaker it would appear that Thomas didn't follow that tradition.
Hope this has been of help & not a hinderence,
Jane