The Six qualities of the Dhamma:
1. Svakkhato: The Dhamma is not a speculative philosophy, but is the Universal Law found through enlightenment and is preached precisely. Therefore it is Excellent in the beginning (Sila — Moral principles), Excellent in the middle (Samadhi — Concentration) and Excellent in the end (Panna — Wisdom),
2. Samditthiko: The Dhamma is testable by practice and known by direct experience,
3. Akaliko: The Dhamma is able to bestow timeless and immediate results here and now, for which there is no need to wait until the future or next existence.
4. Ehipassiko: The Dhamma welcomes all beings to put it to the test and to experience it for themselves.
5. Opaneyiko: The Dhamma is capable of being entered upon and therefore it is worthy to be followed as a part of one's life.
6. Paccattam veditabbo vinnunhi: The Dhamma may be perfectly realized only by the noble disciples who have matured and enlightened enough in supreme wisdom.
(from Anguttara Nikaya 11.12)