Did Jesus explain the bread and cup when He instituted communion in the upper room?
No explanation was given. In the upper room Jesus identified the cup as His blood shed for them and the bread as His body broken, but He offered no explanation and set no criteria for practicing it. Paul later explains its meaning and local-church practice.
Les teaches that in the upper room Jesus said, "Take this cup and this is my blood which will be shed for you," and "this is my body which is broken." Since He had not yet died, it was still future. But Les stresses that even though Jesus did those two things, He gave no explanation and did not institute it as something someone was supposed to do. It is just dropped like a hot potato; you see nothing more of that cup and bread. Les also notes the first instance was Abraham meeting Melchizedek, who brought bread and wine, already a picture of the Lord's table. In the Matthew account Jesus merely said this is the cup of the New Testament and this is my body broken, but no explanation. There was no criteria for how to practice it until Paul tells us what it is all about and how it is to be practiced in the local church. Les further reminds that when Jesus spoke of eating His flesh and drinking His blood in His earthly ministry, many followers left because they could not comprehend, but that was not what He was talking about.
And as they were eating, Jesus took bread, and blessed it, and brake it, and gave it to the disciples, and said, Take, eat; this is my body.
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