Suffering in the will of God challenges us to persevere in our faith. God desires to use such suffering to advance His kingdom and righteousness in many ways, including further conforming us to the image of His Son. We need to keep the right perspective about such suffering:
The tears of those who suffer according to the will of God are spiritual lenses and windows of agate. As the weights of the clock or the ballast in the vessel are necessary for their right ordering, so is trouble in the soul-life. The sweetest scents are only obtained by tremendous pressure; the fairest flowers grow amid Alpine snow-solitudes; the rarest gems have suffered longest from the lapidary’s wheel; the noblest statues have borne most blows of the chisel. All, however, is under law. Nothing happens that has not been appointed with consummate care and foresight.
—F.B. Meyer, Our Daily Homily; bold text is in italics in the original