First Yochanan (1 John) contains some great tools to challenge those who are busy trying to tell people that Y’shua (Jesus) is a myth!
1 John 2: 15. Love not the world nor anything in it; for whoever loves the world has not the love of the Father in him. 16. For all that is in the world is the lust of the body and the lust of the eyes and the pride of the world, which are not from the Father but from the world itself. 17. And the world is passing away, (both) it and the lust thereof; but he that does the pleasure of Elohim abides for ever.
18. My children, it is the latter time; and as you have heard that a false Messiah was to arise, so there are now many false Messiahs; and from this we know that it is the latter time. 19. From us they went out, but they were not of us; for if they had been of us they would have continued with us: but they went out from us that so it might be known that they were not of us. 20. But you have an anointing from the Set Apart (One); and you discriminate every person. (AENT)
 “The world” refers to pagan, Torahless, humanistic, evolutionary, relativistic, materialistic, sensual, unrighteous lifestyles that haSatan used to seduce mankind away from YHWH. This certainly does not refer to the earth which YHWH made according to His good pleasure.
 And the world passes away, and the lust thereof, but he who does the will of Elohim abides forever. 1 John 2:17 (Lamsa). In Aramaic the words for world (alma) and forever (alam) are nearly identically spelled and pronounced. … The pun is also multi-tiered in this case because ancient Jewish thought has always centered on the idea of olam haba, which is literally rendered as “world to come” but figuratively means “world of eternity” or “heaven.”
When confronted with these facts, some theologians suggest that “from the beginning” can mean “from the time of Mashiyach’s ministry”; however, such thinking is easily refuted: “For this is the commandment that you have heard from the beginning, that you must love one another. Not do as Cain did, who belonged to the wicked one and slew his brother.” 1 John 3:11-12 (Lamsa).
If Cain knew this commandment, it must also then go back to Adam. That being the case, the old commandment is very old indeed, and it is rooted firmly in the first book of Torah, known as Genesis!
 As before, “false Messiahs” is used deliberately rather than the proper title of the genuine one, Y’shua the Mashiyach.
1 John 2: 22 Who is a liar at all, if not the person who denies that Yeshua is the Messiah? Such a person is an anti-Messiah - he is denying the Father and the Son. 23 Everyone who denies the Son is also without the Father, but the person who acknowledges the Son has the Father as well.
24 Let what you heard from the beginning remain in you. If what you heard from the beginning remains in you, you will also remain in union with both the Son and the Father. 25 And this is what he has promised us: eternal life.26 I have written you these things about the people who are trying to deceive you.
27 As for you, the Messianic anointing you received from the Father remains in you, so that you have no need for anyone to teach you. On the contrary, as his Messianic anointing continues to teach you about all things, and is true, not a counterfeit, so, just as he taught you, remain united with him.
28 And now, children, remain united with him; so that when he appears, we may have confidence and not shrink back from him in shame at his coming. (CJB)
1 John 4: 1. My beloved, do not believe all spirits; but discriminate among spirits whether they are of Elohim: for many false prophets have gone out into the world. 2. By this the Spirit of Elohim is known; every spirit that confesses that Y’shua the Mashiyach has come in the flesh is of Elohim.
3. And every spirit which does not confess that Y’shua the Mashiyach has come in the flesh is not of Elohim; but he is of the false Messiah of whom you have heard that he comes and now is he already in the world. 4. But you children are of Elohim; and you have overcome them, because greater is he who is in you than he who is in the world.
5. And they are of the world: therefore they speak from the world, and the world hears them. 6. But we are of Elohim; and he that knows Elohim, hears us; and he that is not of Elohim, hears us not. By this, we know the Spirit of Truth and the spirit of error. (AENT)
 The Spirit of Mashiyach dwells inside a person. This does not refer to Y’shua coming in his flesh to Earth; even the demons know that much (see Luke 4:41). This refers to the neshama (spirit of man) being born from the beginning into the image of Elohim, which is evidenced by living a Set Apart life unto YHWH, having Torah written upon the heart and growing in the Attributes of Mashiyach as revealed in Isaiah 11:2.