The Lord Himself, when he shared the Last Supper with His Apostles was celebrating Passover as Jews would. There is no description of their celebration of Passover being changed so that the Apostles would kneel in order to receive Communion on the tongue.
When the Lord said, "Do this in memory of me.", he didn't say "and add kneeling and receiving on the tongue."
Yeah, right. As if you there to witness the Last Supper.
P.S. They were all priests who were present.