Often, the only effort at a biblical criticism is to exclaim, "Judge not, lest ye be judged!" And that is, indeed, biblical, from Matthew 7:1. However, it is not completely biblical. What does the next verse say? "With the judgment you pronounce you will be judged, and with the measure you use it will be measured to you." By what standard will you be judged? By the standard of the Word of God, of course. Thus, Matthew is making the same point that John does in John 7:24: "Do not judge by appearances, but judge with right judgment." That is, judge according to the word of God, not according to one's personal preferences. In both cases, the authors are quoting Jesus. Thus, in context, Jesus in Matthew is not making an absolute statement against exercising judgment. Otherwise we would have Him contradicting Himself.
Later in life, John explained these words of Jesus in his second epistle. He uses the buzzword of the nonjudgmental crowd (that is, nonjudgmental among themselves; they have plenty of judgment for anyone who dares to disagree with them), "love," four times in just the first six verses (out of the mere thirteen in the whole epistle). And I am sure that the love crowd would love to stop at that point. However, John gives a definition of love, one that they will not like (verse six): "this is love, that we walk according to his commandments." "Love," in John's usage, has content.
Another word that John uses a lot in this epistle, five times, is "truth." Not just "a truth," but "the truth," truth that "we know," is "in us," and "abides with us forever." John expresses his joy that the recipients of this epistle are "walking in the truth, just as we were commanded by the Father" (verse 4). In contrast, he warns against "deceivers" (verse 7), who do "not abide in the teaching of Christ" (verse 9), and who we are "not receive him into your house or give him any greeting" (verse 10).
Thus, contrary to the judgment of the love crowd, we are not commanded to love everybody (that is, equally and openly), but rather those who are faithful to the truth, i. e., biblical truth. This is the same attitude that David expresses in Psalm 139:21-22: "Do I not hate those who hate you, O Lord? And do I not loathe those who rise up against you? I hate them with complete hatred; I count them my enemies." The "man after God's own heart" (I Samuel 13:14, Acts 13:22) hated those who hate the truth. And we are, too, regardless of the shrieks of rage from the unloving love hypocrites.