These are the hours when the planet Earth and the self are passing through twilight zones of Time and Space. These hours are from 4am to 7am and 4pm to 7pm. In the morning it is called Amrit Vela in the evening it it called "prayer time."
Any meditation done in a state of unison at that time gives us a clear tomorrow and erases the cause of sorrow which we seed through our thoughts. Through meditation we stand redeemed. It is called Mokosha, Nirvanaa, redemption, or liberation.
The balance we achieve will in the end account for our exit from the planet and for our merger with God, or for our next incarnation.
This, in essence, completes and explains the theory of cause and effect, the theory of reincarnation, the theory of the akashic record, or ava gavan.
-Yogi Bhajan