Is 1 Corinthians 12:3 a Black-and-White Tool for Discernment?

Questions about whether the claim in 1 Corinthians that “no one can say ‘Jesus is Lord’ except in the Holy Spirit” is a black-and-white tool for discernment, and how to have a better relationship with Jesus when reading the Bible feels like a chore and you can’t remember to pray.  

• Since First Corinthians 12:3 says that “no one can say ‘Jesus is Lord’ except in the Holy Spirit,” if TV evangelists who seem to preach another gospel and act overtly un-Christlike claim Jesus is Lord, is that evidence the Holy Spirit dwells in them? Is this a black-and-white tool for discernment?
• How can I have a better relationship with Jesus when reading the Bible feels like a chore and I can never remember to pray? I feel like I don’t know him at all.