Is it possible to get government job after changing religion ?

Job Notification on 2011 , Mr. X and His mother and fathers are hindus in certificate and following Christianity in life.. for marriage 'X' he converted his caste hindu nadar to christian nadar on 2012 and married a christian girl in a church, physical exam for the post conducted at 2014 in that day we shoud ome with our cast certificate ..he get only christian nadar certificate from village office.. then he change his cast again christian nadar to hindu nadar.. and publish a gazate notification he embarazed hinduisam from christian nadar community.. then show the guzzate notification to village officer and officer get a hindu Nadar certificate in 2014 .. he submit that caste certificate to PSC and get Job (reserved for Hindu Nadar ).. now he is working on that job.. iam the next person.. if he is not qualified for HinduNadar reservation .. i get that job.. he argued that he is a Hindu in the time of notification so he is eligible