'Three Jewels' or Three Gems, which by all Buddhists are revered as the most venerable things, are
the Buddha,
the Dhamma and
the Holy Sangha.'
i.e.:
the Enlightened One;
the law of deliverance discovered, realized and proclaimed by him;
and the Community of Holy Disciples and those who live in accordance with the Law. -
The contemplations of the 3 Jewels belong to the 10 contemplations (anussati q.v.).