Related Clues:

• Talked impolitely
• Crossed one's heart
• Used inelegant language
• Promised to tell the truth
• Avowed
• Bore witness (to)
• Vowed
• Promised solemnly
• Cussed
• Took an oath
• Cursed
• Made a statement on a stack of Bibles?
• Prepared to testify
• Made a solemn declaration
• Talked a blue streak?