If a Bible passage wasn't addressed to me, should I ignore it?
No. Scripture should not be discarded simply because it was not originally addressed to you. Instead, determine to whom each passage was written, because the original audience affects what is being said and how it is being said. Address matters for interpretation, but it does not make the rest of Scripture irrelevant.
Les teaches that whenever you read any portion of Scripture, you should always determine to whom it was addressed. He explains that this does not mean that if it was not addressed to you, you throw it aside. Rather, knowing the original audience has an impact on what the passage is saying and how it is being said. He contrasts Paul, who writes to the assembly at Corinth, with Old Testament writers such as Isaiah or Daniel, or the Twelve as they ministered to the nation of Israel. Paul addresses the assembly, the called-out assembly, those sanctified in Christ Jesus and called saints, together with all who call upon the name of Jesus Christ. So audience matters, but the passage is not to be discarded.