The only way to not be deceived by those against Christ is to know and abide in the truth.
1 John 2:18-25
18 Children, it is the last hour; and just as you heard that antichrist is coming, even now many antichrists have appeared; from this we know that it is the last hour.
19 They went out from us, but they were not really of us; for if they had been of us, they would have remained with us; but they went out, so that it would be shown that they all are not of us.
20 But you have an anointing from the Holy One, and you all know.
21 I have not written to you because you do not know the truth, but because you do know it, and because no lie is of the truth.
22 Who is the liar but the one who denies that Jesus is the Christ? This is the antichrist, the one who denies the Father and the Son.
23 Whoever denies the Son does not have the Father; the one who confesses the Son has the Father also.
24 As for you, let that abide in you which you heard from the beginning. If what you heard from the beginning abides in you, you also will abide in the Son and in the Father.
25 This is the promise which He Himself made to us: eternal life.