佛說觀佛三昧海經 5.5

5.5

The Buddha told Ānanda: "Why is it called the Avīci hell? 'A' means without, and 'vīci' means obstruction. 'A' means without, and 'vīci' means rescue. 'A' means interval-less, and 'vīci' means motionless. 'A' means extreme heat, and 'vīci' means extreme anguish. 'A' means relentless, and 'vīci' means ceaseless; relentless and ceaseless is why it is called the Avīci hell. 'A' means great fire, and 'vīci' means intense heat; fierce fire entering the heart is why it is called the Avīci hell."