Then contact and responsive feelings came into existence. Now our rebirth has occurred, we are aging, and all that remains for us is the experience of death. In this life there is no peace, from the time of our birth until our death. All these problems come from karma. Karma comes from ignorance.
Ignorance is the cause of all suffering.
We receive nirvana by cutting off this ignorance, the root of samsara. Without doing this, there is no way to receive nirvana. In order to remove completely the root of samsaric suffering and receive nirvana we must follow a true path. If we do not want to experience true suffering, we should cut off the true cause of suffering. Once we have cut off and removed this root, nirvana is attained.