Aeterna Reddetur Votum was a merciless vow, to say the least. Aside from inflicting an unimaginable amount of pain on its violator, it would also control the cycle of the life force of the individual to prevent it from losing consciousness. To put it succinctly, the vow would never let the violator experience a day without pain until their body decays.
Even though a complete description of the misery under the vow couldn't be obtained, there was an instance when a violator was able to narrate some episodes when he had been interrogated by knights. He was a missionary who claimed that he was forced to believe that the vow was harmless.
