Majjhima Nikaya 4:77
SUJATOYañhissa, bhikkhave, saṁvaraṁ asaṁvutassa viharato uppajjeyyuṁ āsavā vighātapariḷāhā, saṁvaraṁ saṁvutassa viharato evaṁsa te āsavā vighātapariḷāhā na honti.
For the distressing and feverish defilements that might arise in someone who lives without restraint do not arise when there is such restraint.