Events are held across Wales, including a Spitfire flypast in Caerphilly and a parade in Wrexham.
Among the "impressive and talented group", five are ordained as deacons and four as priests.
Road closures and parking arrangements will be in place as thousands head to Wrexham's Racecourse Ground.
Lions coach Warren Gatland says Liam Williams would assess his performance in their first Test defeat by New Zealand as "mixed".
Geraint Thomas says it has been mentally tough to recover from a partially dislocated shoulder suffered at the Giro d'Italia.
North Wales Daily Post
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