A figure of speech consists of a word of words used out of the ordinary sense, or order; just as we call a person dressed out of the ordinary manner or fashion a "figure":  both attract our attention; and, in the case of words, the one and only object is in order to call a reader's attention to what is thus emphasized.  For examples see the notes on Matt. 16:6; where, had the Lord said "the doctrine of the Pharisees is like leaven", that would have been the Fig. Simile (Ap. 6).  Had He said "the doctrine of the Pharisees is leaven", the Fig. in this case would have been Metaphor (Ap. 6); by which, instead of saying one thing is like another, it is carried over (as the word Metaphor means), and states that the one thing is the other.  But in Matt. 16:6, the Lord used another Figure altogether, viz. Hypocatastasis (from hupo = under (Ap. 104. xviii), kata = down (Ap. 104. x), and stasis = a stationing), which means putting one of the two words (which are necessary in the case of Simile and Metaphor) down underneath, i.e. out of sight, and thus implying it.  He said, "beware of the leaven", thus implying the word "doctrine", which He really meant; and, by thus attracting the disciples' attention to His words, thereby emphasized them.

In these three Figures we have a Positive, Comparative, and Superlative emphasis.  The essence of Simile is resemblance; the essence of Metaphor is representation (as in the case of a portrait, which is representation of some person); the essence of Hypocatastasis is implication, where only one word is mentioned and another is implied.

Through non-acquaintance with Figures of Speech every Figure is to-day called a "Metaphor".  But this is not the case.  A Metaphor is a special Figure different and distinct from all others.

"This is My body" is the Figure Metaphor; and the Figure lies in the Verb "IS", which, as in this case always means "represents", and must always be so expressed.  It can never mean "is changed into".  Hence in the Figure Metaphor, the Verb "represents" can always be substituted for "is".  For example:

"The field is (or represents) the world"  (Matt. 13:38).

"The good seed are (represent) the sons of the kingdom"  (Matt. 13:38).

"The reapers are (represent) angels"  (Matt. 13:39).

"The odors are (represent) the prayers of the saints"  (Rev. 5:8).

"The seven heads are (represent) seven mountains"  (Rev. 17:9).

"This cup is (represents) the new covenant"  (1Cor. 11:25).

"The cup of blessing which we bless, is it not (does it not represent) the blood of Christ?"  (1Cor. 10:16).

Furthermore, it is a fundamental law in Greek grammar, without exception, that the Article, Pronoun, and Adjective must agree in gender with the Noun to which they refer.  For example, in Matt. 16:18, the Pronoun "this" is Feminine, and thus agrees with petra, which is also Feminine, and not with petros (Peter) which is Masculine.  See note, and Ap. 147.

So here :  the Pronoun "this" is Neuter, and cannot agree with artos ( = bread) because artos is Masculine.  It must refer to what is Neuter; and this could only be the whole act of breaking the bread, which would be Neuter also; or to klasma, the broken piece (which is also Neuter).

In like manner, when He said (in v. 28) "this is my blood of the New Covenant"; "this", being Neuter, refers to poterion ( = cup) (*1) and not to oinos ( = wine), which is Masculine, and means :-- "This [cup] represents My blood of the New Covenant, which is poured out for many, for remission of sins".

For, what was the Lord doing?  He was making the New Covenant foretold in Jer. 31:31-34.  If it were not made then, it can never be made at all (see Ap. 95), for no more has He blood to shed (Luke 24:39).

Now, "blood" was shed, and sacrificially used, only in connection with two things, making of a covenant, and the making of atonement.  In the former, the victim which made or ratified the covenant was slain and the body divided in two, the parties to the covenant passing between (see notes on Gen. 15:9-18.  Jer. 34:18.  Gal. 3:20.  and Ap. 95).  As long as the victim (the covenant maker) was alive the covenant could have no force.  See notes on Heb. 9:16-22.

At the last supper this New Covenant was made; and Peter's proclamation in Acts 2:38;  3:19-26;  5:31;  and Paul's in 13:38;  17:30;  20:21;  26:20; were based upon it.  Messiah had to be "cut off", that the Scriptures might be fulfilled (Acts 3:18).  But that having been accomplished, and the sufferings having been endured, nothing stood in the way of the glory which should follow.  "Repent ye THEREFORE and turn [to the Lord] that your sins may be blotted out", &c.  The New Covenant which had been made had provided for that, as the Lord had said in Matt. 26:28, "for the remission of sins".

In that last supper the Lord was not instituting anything with a view to the Secret (the "Mystery" to be yet revealed in the Prison Epistles);  but was substituting bread and wine for the Paschal Lamb (the type being exhausted in the Antitype), because of the new meaning which the Passover should henceforth convey.  It was to be the Memorial, not of the Exodus from Egypt, but of the Exodus which the Lord afterward accomplished in Jerusalem (Luke 9:31), according to the New Covenant made by His death.

(*1) Poterion being put by Metonymy (of Adjunct), Ap. 6, for the contents, for the "cup" itself could not be swallowed.