A morning hymn (st. 1) as well as an evening hymn (st. 4), the text presents praise to Christ from angels and human creatures (st. 2) and from the elements of earth to the farthest reach of the cosmos (st. 3). In fact, this text is for all times and places: "Be this the eternal song"!
Psalter Hymnal Handbook
What can possibly be so important that it is our first cry in the morning and our last thought at night? Belgic Confession, Article 20 testifies that God gave us “…his Son to die by a most perfect love” and then raised him to life “for our justification in order that by him we might have immortality and eternal life.”
Because of such perfect love, comfort can be found in the words of Heidelberg Catechism, Lord’s Day 1, Question and Answer 1: “I belong—body and soul, in life and in death—to my faithful Savior Jesus Christ.” This is our cry—first thing in the morning and last thought at night!