Arcana Coelestia # 527
527. That Lamech means a Church in which the perception of truth and good was so general and vague as to be almost none at all, and so it was a vastated Church, becomes clear from what has gone before and from what follows, for the very next verse contains a description of it. In the previous chapter 'Lamech' had almost the same meaning as he does here, namely vastation; see verses 18, 19, 23-24, of that chapter. And the one who beget him even bore a similar name, which was Methusael. Consequently things that were almost the same were meant by these names; Methusael and Methuselah both mean something that is about to die, while Lamech means that which has been destroyed.
John 15:16
16
You didn't choose me, but I chose you, and appointed you, that you should go and bear fruit, and that your fruit should remain; that whatever you will ask of the Father in my name, he may give it to you.