Textual criticism is a highly technical discipline. Ordinary pastors can’t hope to know everything about the subject. But, they can pay attention in Seminary and read enough to be familiar with the basic issues. The congregation has notes in their margins or footnotes, telling them all about Acts 8:37, John 7:53 - 8:11, John 5:7-8 and Mark 16:9-20. A pastor needs to know enough to answer the more obvious questions these footnotes will generate.
In my opinion, these are some very useful tools to help: