Adam Clarke on Psalms 55:17

Evening, and morning, and at noon, will I pray - This was the custom of the pious Hebrews. See Dan 6:10. The Hebrews began their day in the evening, and hence David mentions the evening first. The rabbins say, Men should pray three times each day, because the day changes three times. This was observed in the primitive Church; but the times, in different places, were various. The old Psalter gives this a curious turn: "At even I sall tel his louing (praise) what tim Crist was on the Crosse: and at morn I sall schew his louing, what tim he ros fra dede. And sua he sall here my voyce at mid day, that is sitand at the right hand of his fader, wheder he stegh (ascended) at mid day."