From the Arcana Coelestia #4735

Among the Ancients ‘flesh and blood’ meant the human proprium, for that which is human consists of flesh and blood. This explains what the Lord said to Simon,

Blessed are you, for flesh and blood has not revealed this to you, but My Father who is in heaven. Matt. 16:17.

Therefore the flesh and blood meant in the Holy Supper by the bread and wine are the Lord’s Human Proprium. The Lord’s actual Proprium which He acquired to Himself by His own power is Divine. His Proprium was since His conception that which He had from Jehovah His Father and was Jehovah Himself, and therefore the Proprium which He acquired to Himself within the Human was Divine. It is this Divine Proprium within the Human that is called flesh and blood, ‘flesh’ being His Divine Good, 3813, ‘blood’ Divine Truth that goes with Divine Good.

[2] The Lord’s Human, now that it has been glorified or made Divine, cannot be thought of as something merely human but as Divine Love within a human form. This is more true of Him than it is of angels, who – when they come to be seen, as I myself have seen them – are seen as forms of love and charity taking on a human appearance, the Lord enabling this to be so. For it was by Divine Love that the Lord made His Human Divine, even, as has been stated, as heavenly love serves to make someone an angel after death, so that he too is seen as a form of love and charity taking on a human appearance. From this it is evident that in the celestial sense the Lord’s Divine Human means Divine Love itself, which is a love directed towards the whole human race whom He wishes to save, making them blessed and happy for ever, and to whom He wishes to impart, insofar as its members can accept it, what is His and is Divine, so that it becomes their own. This love, and man’s reciprocated love to the Lord as well as his love towards the neighbour, are meant and represented in the Holy Supper, Divine celestial love by the flesh or bread in it and Divine spiritual love by the blood or wine.

[3] From all this one may now see what is meant by eating the Lord’s flesh and drinking His blood in John,

I am the living bread which came down from heaven. If anyone eats of this bread he will live for ever. But the bread which I shall give is My flesh. Truly, truly, I say to you, Unless you eat the flesh of the Son of Man and drank His blood you will have no life in you. He who eats My flesh and drinks My blood has eternal life, and I will raise him up on the last day. For My flesh is truly food, and My blood is truly drink. He who eats My flesh and drinks My blood abides in Me, and I in him. This is the bread which came down from heaven. John 6:50-58.

Because ‘flesh’ and ‘blood’ mean the Divine Celestial and the Divine Spiritual that proceed from the Lord’s Divine Human, as has been stated, or what amounts to the same, mean Divine Good and Divine Truth that proceed from His Love, ‘eating’ and ‘drinking’ mean making these things one’s own. They become one’s own through the life of love and charity which is also the life of faith. For ‘eating’ means making good one’s own, and ‘drinking’ making truth one’s own, see 2187, 3069, 3168, 3513, 3596, 3734, 3832, 4017, 4018.