Pessimistic Optimism
If we look at the Bible from the widest angle, several things are clear. Its scope is everything, as it comes from God and, by His grace, aheads back to His reign. The end matches, fulfills, and surpasses the beginning.
But the plot of that arrival is a battle, a struggle. The conclusion is a victory, and the conqueror is the wounded lamb Jesus Christ, who also resides at the center of the story.
And books like Daniel and Revelation confirm that signs of that victory are plague, persecution, distress...and the preaching of good news! (Revelation 19:11). Take courage- things will get worse before they get I describably better, for only for a fixed time set by God (Daniel 7:25). All this illumines the mixture of pessimism and hope of the believer hard for the worldly mind to fathom.