And what is the factor of trying to be pure in view? Take a mendicant who truly understands: ‘This is suffering’ … ‘This is the origin of suffering’ … ‘This is the cessation of suffering’ … ‘This is the practice that leads to the cessation of suffering’. This is called purity of view. They think: ‘I will fulfill such purity of view, or, if it’s already fulfilled, I’ll support it in every situation by wisdom.’ Their enthusiasm for that—their effort, zeal, vigor, perseverance, mindfulness, and situational awareness—is called the factor of trying to be pure in view.

And what is the factor of trying to be pure in freedom? That noble disciple—who has these factors of trying to be pure in ethics, mind, and view—detaches their mind from things that arouse greed, and frees their mind from things that it should be freed from. Doing so, they experience perfect freedom. This is called purity of freedom. They think: ‘I will fulfill such purity of freedom, or, if it’s already fulfilled, I’ll support it in every situation by wisdom.’ Their enthusiasm for that—their effort, zeal, vigor, perseverance, mindfulness, and situational awareness—is called the factor of trying to be pure in freedom.

These four factors of trying to be pure have been rightly explained by the Blessed One, who knows and sees, the perfected one, the fully awakened Buddha. They are in order to purify sentient beings, to get past sorrow and crying, to make an end of pain and sadness, to discover the system, and to realize extinguishment.”

Numbered Discourses 4.195 20. The Great Chapter With Vappa

At one time the Buddha was staying in the land of the Sakyans, near Kapilavatthu in the Banyan Tree Monastery. Then Vappa of the Sakyans, a disciple of the Jains, went up to Venerable Mahāmoggallāna, bowed, and sat down to one side. Mahāmoggallāna said to him: