Hi Keith
If you get too many of these Scottish folks (especially post 1855) - you are going to learn to hate English Certificates. You will also discover the joys of being able to download a certificate online for one pound. Thus said - at one stage SP owned my credit card - it was just too easy

Before spending your life's savings my small piece of advice:
I have found the IGI very good for Scotland and only found a few parish records for my folks on SP that weren't on the IGI (Of course this didn't stop me spending my money to look

). Civil indexes 1855 to 1875 (& a couple of other odd years) are also on the IGI.
If you are searching on SP for census data, some Scottish ladies are listed in their maiden name (that caused me grief for awhile, but once found was VERY useful).
Your location is probably a small locality near Dolphinton, given that was where your man was christened. I have found similar localities in the past (with help from RC) via oldmaps. If I can find the website I will check.
Your register entry is quite intriguing as to why the mininster's details are where they are

Presumably because of the name. As his given name was John, perhaps this is why your ancestor started using the name.
There is a Bridgend in Lanark from old maps - Grid Ref: 268500,670500
whether it is yours or not? Dolphinton (I don't think there is a "g" in it) is Grid Ref: 310500,646500
Trish