1003. That 'not eating flesh with its soul, its blood' means not mixing together unholy things with holy is now clear from what has been stated above. Unholy things are in no way mixed with holy through somebody's eating blood along with the flesh, as also the Lord clearly teaches in Matthew,
Not what goes into the mouth renders a man unclean, but what comes out of the mouth, this renders the man unclean. For the things which come out of the mouth come out of the heart. Matt. 15:11, 17-20.
It was prohibited in the Jewish Church however because in heaven, as stated, eating blood along with the flesh in those days represented profanation. Everything that took place in that Church was converted in heaven into corresponding representatives. Blood in particular was converted into that which is holy and celestial, while flesh, with the exception of that offered in sacrifices, was converted into that which is unholy, because, as has been shown, it meant evil desires. The mere eating of the two in those times was converted into a mixing together of what is holy and of what is unholy. This was why the practice was so strictly forbidden in those days. But after the Lord's Coming when external rites were abolished and so representatives came to an end, such things ceased after that to be converted in heaven into corresponding representatives. For when a man becomes internal, and has been informed concerning internal things, external things are of no importance to him. He is now aware of what holiness really is, namely, charity and faith deriving from it. Things with him which are external he now regards from the viewpoint of charity and faith, that is to say, he looks to see how much charity and faith in the Lord external things contain. This is why since the Lord's Coming heaven has looked at mankind not from the viewpoint of external things but of internal. And if anyone is looked at from the viewpoint of those things that are external it is because he dwells in simplicity, and in innocence and charity within that simplicity. These are present with him from the Lord in external things, that is, in his external worship, though he himself is not actually aware of this.