The Church of today is in serious trouble and it is sad, indeed, because it is in trouble for the lack of God Fearing Men in the Pulpit, by and large. But the Church is in the mess most of all because people will not study to show themselves approved! (2Tim, 2:15) People calling themselves Christian run around spouting ideologies that they never, even, pretend are backed by the scriptures. In the case of Matthew 7:1 the World committed Spiritual Rape on the seventh chapter and ripped verse 1 from it's context of cleansing oneself of sin before judging another for sin and some narrow it further and say it means you must be free of that sin. For this Conservative Christian the later is to open ended.
How do I know this? Thank you for asking that question, it is important. In the days of and just before the First Century, there were no paragraphs, shoot, they did not even use page breaks, it was one long paragraph until the point was made or the tale was over.
Today people have noted subject change and they split the Books of the Bible into chapters and verses and they numbered both, much easier to read than one long sentence from the beginning with one period at the end, if they had one.
These men somewhere before or in the Seventeenth Century were Bible Scholars and if you will look in a copy that is paragraphed or has the funny little symbol in front of some of the verses that I ever, as a kid, learned tlo pronounce because it marks the beginning of another paragraph. That strange looking Pilcrow marks paragraphs or changes in the line of thought.
As I recall the first six verses compose the first paragraph and if you read that paragraph instead of just the opening remark it becomes clear that Jesus is teaching us to use our ability, as children of
God to Discern Good from Evil, judging, but first make sure we are not guilty before God.
To learn how to know when you are in good standing with God you will need to dig into sin and learn to tell the difference between Accidental Sin and intentional Sin. I recommend the Nave's Topical Bible and look up Sin and read all of the noted scriptures and pray before and after or God; s discernment in the issue.