True Presence = in Holy Communion Christ's actual body given for us and His real blood shed for us on his cross are received by the communicant along with the bread and wine. His true body and blood are present not because I receive the cracker and wine with a sincere heart, but because Christ has promised that we will receive his body and blood whenever we partake of Holy Communion.
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.And he took the cup, and gave thanks, and gave it to them, saying, Drink ye all of it;For this is my blood of the new testament, which is shed for many for the remission of sins.
And as they did eat, Jesus took bread, and blessed, and brake it, and gave to them, and said, Take, eat: this is my body.And he took the cup, and when he had given thanks, he gave it to them: and they all drank of it.And he said unto them, This is my blood of the new testament, which is shed for many.
And he took bread, and gave thanks, and brake it, and gave unto them, saying, This is my body which is given for you: this do in remembrance of me.Likewise also the cup after supper, saying, This cup is the new testament in my blood, which is shed for you.
1 Cor. 11:23-26
For I have received of the Lord that which also I delivered unto you, That the Lord Jesus the same night in which he was betrayed took bread:And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me.After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me.For as often as ye eat this bread, and drink this cup, ye do shew the Lord's death till he come.
Martin Luther writes in the small catechism:
Christ’s words in the Sacrament must be taken at face value especially because:
A. These words are the words of a testament, and even an ordinary person’s last will and testament may not be changed once that person has died;
1 Cor. 11:25
After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me.
Brethren, I speak after the manner of men; Though it be but a man's covenant, yet if it be confirmed, no man disannulleth, or addeth thereto.
B. God’s Word clearly teaches that in the Sacrament the bread and wine are a communion or participation in the body and blood of Christ;
1 Cor. 10:16
The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ?
C. God’s Word clearly teaches that those who misuse the Sacrament sin not against bread and wine but against Christ’s body and blood.
1 Cor. 11:27-29
"Wherefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord.But let a man examine himself, and so let him eat of that bread, and drink of that cup.For he that eateth and drinketh unworthily, eateth and drinketh damnation to himself, not discerning the Lord's body."
If I commune with faith in Christ's promise (that the bread and wine are also His body and blood), or lack thereof, will determine whether I receive those gifts to my blessing or to my judgment.
This is not RCC's transubstantiation which goes beyond Scripture to try to come up with a "magical" explanation of "how" the body and blood of Christ are present together with the bread and wine.
True Presence simply echos what Scripture says: according to Jesus' promise we receive four things whenever we commune (bread and wine, Christ's body and blood).