(AI Generated Summary) This sermon examines Luke 21:27 as the climactic point of the Olivet Discourse, arguing that the return of the Son of Man is a visible, cosmic event rather than a secret or invisible occurrence. The text contrasts the humble, hidden nature of Christ's first coming, which accomplished redemption through substitutionary death, with the resplendent glory and power of His second coming, which will be witnessed by all nations. By refuting interpretations that suggest a secret rapture or an invisible 70 AD fulfillment, the message emphasizes that the Day of the Lord will be marked by supernatural signs and universal recognition. The sermon concludes with a pastoral exhortation to believers to stand firm in faith and persevere in their earthly pilgrimage, anchored by the blessed hope of Christ's visible return and the transformation of their bodies.