'Spent' in the Bible

The [mournful, inspired] oracle (a burden to be carried) concerning Dumah (Edom):Someone keeps calling to me from Seir (Edom),“Watchman, what is left of the night [of Assyrian oppression]?Watchman, what is left of the night? [How long until morning?]”

Then I said, “I have labored in vain,I have spent My strength for nothing and vanity (pride, uselessness);However My justice is with the Lord,And My reward is with My God.”