You know what justifies sending people to hell?
Because if there is a God that has a standard for what is good and what is evil, and if he cannot be around evil, and you are evil, you cannot be around God.
God's love isn't apparent from His necessary justice upon sin; it's apparent from His solution.
If you have any questions you want explained biblically, the Help/FAQ search database at Blue Letter Bible - Home Page is amazing and will likely give you a topic with verses over exactly what you question.
Blue Letter Bible - Help, Tutorials, and FAQs
Blue Letter Bible - Help, Tutorials, and FAQs
Blue Letter Bible - Help, Tutorials, and FAQs
I'd say who best explains questions like these are people like Dr. Ravi Zacharias who gives presentations at Harvard and other prestigious schools about Christianity.
Look him up on YouTube
These two video might interest you in particular, as he answered a question of a student at Harvard
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Another good one
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