The LORD our Passover

From here on is the discourse of the events during and just after this last meal. John carries these things on in much depth and brevity of conciseness, under the influence of the Holy Spirit for our learning of Him, Christ Jesus and ultimate understanding of His revelation. I will only do through chapter 14 to keep this short because of the depth of meaning and revelation of Christ Jesus as our LORD, revealed by John through the rest of his account of the events as they followed.
Jesus' washing of the disciple's feet before the partaking of the Last Supper (in chapter 13 through 14) after which He foretells of His impending betrayal and death and His preparing of a place for those who do as He is about to do, by way of example, in the physical to remove the stain and chains of mans natural estate. This action is another one of those which expose us to becoming united through washing away the dirt of the world which clings to the outside of the cup or vessel.

“Before the feast of the passover, when Jesus knew that His hour was come that He should depart out of this world to return to the Father, having loved His own which were in the world, for He loved them to the end. And supper being ended, the devil having now put into the heart of Judas Iscariot, Simon's son, to betray Him; Jesus knowing that the Father had given all things into His hands, and that He was come from God, and went (return) to God; He rose from supper, and laid aside His garments; and took a towel, and girded Himself. After that He poured water into a basin, and began to wash the disciples' feet, and to wipe them with the towel wherewith He was girded. When He came to Simon Peter: and Peter said to Him, Lord, do You wash my feet? Jesus answering said to him, What I do you know not now (you do not now understand); but you shall know hereafter. To this Peter said to him, You shall never wash my feet. Jesus answered him, If I wash you not, you have no part with Me. Then Simon Peter said to Him, Lord, not my feet only, but also my hands and my head. Jesus then said to him, He that is washed needs not save to wash his feet, but is clean every bit: and you are clean, but not all. For He knew who should betray Him; therefore He said, You are not all clean. (Ezekiel 36:(25-26) 22-32) 

After He had washed their feet, and had taken His garments, and was set down again, He said to them, Know you what I have done to you? Because you call Me Master and LORD: and you say well; for I AM. (signifying what Exodus 3:14-15 reveals Him) If I then, I AM your Lord and Master, have washed your feet; you also ought to wash one another's feet. For I have given you an example, that you should do as I have done to you. Verily, verily, I say to you, The servant is not greater than his lord; neither is He who is sent greater than He that sent Him.(signifying that He is indeed both the LORD and Father in Elohim) If you know these things, happy are you if you do them. I speak not of you all: I know whom I have chosen (Heb. 4:13, Rom. 11:25-36, Rev. 2:23): but that the scripture may be fulfilled, He that eats bread with Me has lifted up his heel against Me. (Psalm 41:9) Now I tell you before it comes, that, when it is come to pass, you may believe that I am He. Verily, verily, I say to you, He that receives whomever I send receives Me; and he that receives Me receives Him that sent Me.

When Jesus had thus spoken these things, He was troubled in spirit, and testified, and said, Verily, verily, I say to you, that one of you shall betray Me. Then the disciples looked one on another, doubting of whom He spoke of. Now there was leaning on Jesus' bosom one of His disciples, whom Jesus loved. Simon Peter therefore beckoned to him, that he should ask who it should be of whom He had spoken of. He then lying on Jesus' breast said to Him, Lord, who is it? Jesus answered, He it is, to whom I shall give a sop, when I have dipped it. When He had dipped the sop, He gave it to Judas Iscariot, the son of Simon. Immediately after the sop Satan entered into him. Then said Jesus to him, That which you do, do quickly. No man at the table knew for what intent He spoke this to him. For some of them thought, because Judas had the bag, that Jesus had said to him, Buy those things that we have need of against the feast; or, that he should give something to the poor. He then having received the sop went immediately out: and it was night. 

Therefore, when he was gone out, Jesus said, Now is the Son of man glorified, and God is glorified in Him. If God be glorified in Him, God shall also glorify Him in Himself, and shall straightway glorify Him. Little children, yet a little while I am with you. You shall seek Me: and as I said to the Jews, Where I go, you cannot come; so now I say to you. A new commandment (Jeremiah 31:31-33, 34, Galatians 6:2, 1John 2:8-10) I give to you, That you love one another; as I have loved you, that you also love one another. By this shall all know that you are My disciples, if you have love one to another.(John 15:13, 17:21, 1John 4:7-11, 20-21)