Judas was most certainly "a disciple" of the Lord Jesus, if by that term be meant, as is usually understood, the twelve whom he chose to be constantly with him. This is most plain from Matthew 10:1, Luke 6:13, and Luke 9:1; from which places it is undeniable that Judas was not only a disciple, but an apostle, and was sent by the Lord himself to cast out devils, cure diseases, and preach the gospel.
We well know that he was not a "disciple indeed" (John 8:31); but as regards his outward mission he was as much a disciple as John, and as much an apostle as Peter.
But there is no reason to believe that Judas was present at the Lord's supper. He was present at the eating of the Passover, and it was most probably in the sauce eaten with the paschal lamb, which was made thick, as an emblem of the clay of Egypt, of which the bricks were made, that the Lord dipped the sop which he gave to Judas.
Directly he had taken the sop, Judas went out (John 13:30); and then it was, immediately after his departure, that the Lord instituted the Lord's supper, by blessing and breaking the bread, and afterwards blessing and distributing the wine.
By J.C. Philpot