Mahāvagga

Suttapiṭaka · Khuddakanikāya · Paṭisambhidāmagga · Vol. 31 · Section 273

[273] "Easy to make understand, hard to make understand" (suviññāpaye duviññāpaye): a person with faith (saddhā) is one easy to make understand; a person without faith is one hard to make understand. A person of aroused energy (āraddhavīriya) is one easy to make understand; a lazy person (kusīta) is one hard to make understand. A person with mindfulness established (upaṭṭhitassati) is one easy to make understand; a person of muddled mindfulness (muṭṭhassati) is one hard to make understand. A concentrated person (samāhita) is one easy to make understand; an unconcentrated person is one hard to make understand. A wise person (paññavā) is one easy to make understand; a person of poor wisdom (duppañña) is one hard to make understand.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.