Related Clues:

• Mark, for one
• 'Really!'
• 'Truly!'
• 'I swear!'
• Music genre
• Grammy category
• Doctrine
• 'And that's ___' ('Believe you me')
• 'Really?'
• 'I'm telling the truth!'
• Ain't it the truth
• 'I'm not kidding!'
• Mass communication?
• ''It's the truth''
• Holy book