The anguish of the Lord of the vineyard as He beholds, from time to time, the decline of his trees and the lack of good fruit is reflected in the question just cited (repeated also in verses 47 and 49). The same theme is sounded in a parable from Isaiah: “What could have been done more to my vineyard, that I have not done in it? wherefore, when I looked that it should bring forth grapes, brought it forth wild grapes?” (Isaiah 5:4; see 2 Nephi 15:4). The doctrine behind the allegory is the certainty of God’s unremitting service on behalf of His children, whose immortality and eternal life constitute His mission and His glory (see Moses 1:39). God will never give up the fight. The forward motion of the plan is inexorable, despite disappointments and reversals along the way. Elder Neal A. Maxwell confirms this truth: “Prophets have a special appreciation, too, for Jacob’s allegory of the olive trees. They can identify with the feelings of the Lord of the vineyard who, after all His labors, saw much evil fruit come forth. The twice-given lamentation of the Lord of the vineyard was: ‘What could I have done more for my vineyard?’ (Jacob 5:41, 47.)” (If Thou Endure It Well [Salt Lake City: Bookcraft, 1996], 72.)
We, too, sometimes might feel that our labors are not fully productive when children stray from the path or when our missionary outreach is not welcomed by those whom we try to teach. In such cases, the allegory of Zenos lends comfort and hope to our efforts, since, in the broad contours of God’s plan for His children there will be the ultimate harvest of joy and triumph. From our modest position as servants of the Lord, we realize that our efforts will bear fruit if we endure to the end and place our faith in the “Lord of the harvest” (Alma 26:7).