Reference request: where is this text about abandoning hindrances from?

I found the text below on another site. However, it doesn't say whether the source is a specific sutta, commentaries or something else. Could someone show me the origin? >Six things are conducive to the abandonment of restlessness and remorse: >1. Knowledge of the Buddhist scriptures (Doctrine and Discipline); 2. Asking questions about them; 3. Familiarity with the Vinaya (the Code of Monastic Discipline, and for lay followers, with the principles of moral conduct); 4. Association with those mature in age and experience, who possess dignity, restraint and calm; 5. Noble friendship; 6. Suitable conversation. https://www.accesstoinsight.org/lib/authors/nyanaponika/wheel026.html