O send thy light forth and thy truth

O send thy light forth and thy truth. Scottish Psalter*.  These well known stanzas paraphrase verses 3-5 of Psalm 43. In the Scottish Psalter of 1650, The Psalmes of David in Meeter, the text was as follows:  O send thy light forth, and thy truth:  let them be guides to me, And bring me to thine holy Hill,  ev’n where thy dwellings be.  Then will I to Gods altar go,  to God my chiefest joy: Yea, God, my God, thy Name to praise  my harp I will employ.  Why art thou then cast down, my soul?  what should discourage thee? And why, with vexing thought, art thou  disquieted in me?  Still trust in God, for him to praise  good cause I yet shall have; He of my countenance is the health,  my God...