The things people do to get a response, eh?
Obviously, he did observe it because He rose that morning and came to be with his disciples in the upper room (Mark, Luke and John.) He showed them his hands, his feet and his side.
Luke 24:36-43
36 While they were telling these things, He Himself stood in their midst and said to them, “Peace be to you.” 37 But they were startled and frightened and thought that they were seeing a spirit. 38 And He said to them, “Why are you troubled, and why do doubts arise in your hearts? 39 “See My hands and My feet, that it is I Myself; touch Me and see, for a spirit does not have flesh and bones as you see that I have.” 40 And when He had said this, He showed them His hands and His feet. 41 While they still could not believe it because of their joy and amazement, He said to them, “Have you anything here to eat?” 42 They gave Him a piece of a broiled fish; 43 and He took it and ate it before them.
This person will not understand because they are seriously indoctrinated into their teachings and Easter was not celebrated the way we know it now because Jesus had shown himself raised from the grave. Different practices for Easter developed slowly over the years.
Another thing that the SDA;s think is that Constantine was the one who changed the worship from Saturday to Sunday. Justin Martyr tells us that it was in the first century that people celebrated it on the Monday after His resurrection.
It just popped into my head that they also think that the Easter practices that we have also came from Constantine’s conversion to Christianity. There are many SDA’s who do celebrate Easter, too.