In Anguttara nikaya there is a Sutta called Pacalayamana Sutta which is about Venerable MahaMoggallana's attainment of Arahatta. In this Sutta there is one instruction to the Venerable MahaMoggallana by the Buddha to create the Aloka light both in day and in night to overcome sloth & torpor (ThinaMiddha) The Buddha also taught in Aloka Sutta and Abha Sutta of Anguttara Nikaya that there are 4 kinds of light: 1) sunlight, 2) moonlight (which includes starlight), 3) light of fire, and 4) light of wisdom. As for the light of wisdom the subcommentary to the Pacalayamana Sutta mentioned that there are 4 types:1) Dibba Cakkhu Abhinna (Divine eye/psychic power) also has light. 2) Aloka Kasina or all the Kasina have light. 3) Beginning from Palikamma Samadhi (preliminary concentration) which is close to Upacara Samadhi up till the upper Samatha Bhavana Citta, all these have light also. 4) In the Upakilesacalled Vipassanobhasa - it is the bright light of Vipassana nana(Vipassana insight knowledge).
- Pa Auk Sayadaw
To study is to know the texts,
To practice is to know your defilements,
To attain the goal is to know and let go.
- Ajahn Lee Dhammadharo
With mindfulness immersed in the body
well established, restrained
with regard to the six media of contact,
always centered, the monk
can know Unbinding for himself.
- Ud 3.5