There are plenty of triumphant moments in the Bible: the exodus, David’s many victories, the building of the Temple, the return from exile, the coming of the Messiah with authority, power, and healing, and the apostles healing and converting huge groups of people.
But all of these Biblical triumphs are matched and followed by declines and disappointment. The people build a golden calf and God gives up on them (it’s Moses who convinces God not to). David’s dynasty is a big mess of intrigue, rebellion, and division, Jerusalem is conquered and its leaders exiled, and then the exilic hope fades when Zerubbabel dies and the Greeks conquer them. Jesus’ healing power becomes thwarted as his ministry progresses: the disciples continue to not understand even at the second miraculous feeding, the blind man in Mark 8:22-26 requires a second touch, and the disciples fail to exorcise a spirit in 9:14-19: you unbelieving generation! is all Jesus can say (9:19). The disciples will want honor and glory in Jesus’ coming kingdom, and they will scatter at his arrest and crucifixion. The book of Acts will end limply, with Paul preaching while imprisoned, and the movement seemingly stifled.
It’s easy to think of Christianity as triumphalistic in its proclamation of Jesus’ resurrection and new kingdom, but more than anything it is soberly realistic. Even the best of actions result in mixed results and reactions, and there is a resistance and a growing unbelief. There is trust that God will resolve things in the end, but the manner of that resolution remains unknown.