roni wrote:"With a gladdened mind observe the observance day (uposatha), complete with its eight factors, on the fourteenth, fifteenth and eighth days of the (lunar) fortnight and also the special holiday of the half month."
Hi Roni,
First of all I see that is your first post here, so Welcome to Dhamma Wheel!
In ancient times, the 8 precepts were taken on the four main phases of the moon, including the New and Full.
Today, many take just on the New and Full or even just on the Full moon.
The 8 precepts:
1. Panatipata veramani sikkhapadam samadiyami
* I undertake the precept to refrain from destroying living creatures.
2. Adinnadana veramani sikkhapadam samadiyami
* I undertake the precept to refrain from taking that which is not given.
3. Abrahmacariya veramani sikkhapadam samadiyami
* I undertake the precept to refrain from sexual activity.
4. Musavada veramani sikkhapadam samadiyami
* I undertake the precept to refrain from incorrect speech.
5. Suramerayamajja pamadatthana veramani sikkhapadam samadiyami
* I undertake the precept to refrain from intoxicating drinks and drugs which lead to carelessness.
6. Vikalabhojana veramani sikkhapadam samadiyami
* I undertake the precept to refrain from eating at the forbidden time (i.e., after noon).
7. Nacca-gita-vadita-visukkadassana mala-gandha-vilepana-dharana-mandana-vibhusanathana veramani sikkhapadam samadiyami
* I undertake the precept to refrain from dancing, singing, music, going to see entertainments, wearing garlands, using perfumes, and beautifying the body with cosmetics.
8. Uccasayana-mahasayana veramani sikkhapadam samadiyami
* I undertake the precept to refrain from lying on a high or luxurious sleeping place.
(from Anguttara Nikaya 8.41)