15 “You open Your Hand, and fill every living thing with blessing”. Though sometimes You give not, yet “in due season” You give: You delay, not deny, and that in due season. “Righteous is the Lord in all His ways, and holy in all His works”. Both when He smites and when He heals, He is righteous, and in Him unrighteousness is not. Finally, all His saints, when set in the midst of tribulation, have first praised His righteousness, and so sought His blessings. They first have said, “What You do is righteous.” So did Daniel ask, and other holy men: “Righteous are Your judgments: rightly have we suffered: deservedly have we suffered.” They laid not unrighteousness to God, they laid not to Him injustice and folly. First they praised Him scourging, and so they felt Him feeding.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)