Mike Bickle emphasizes the supremacy of Jesus in his sermon based on Hebrews 1:1-3, highlighting that Jesus is the heir of all things, the creator of the universe, and the exact representation of God's glory. He explains that understanding Jesus' magnificence transforms our emotions and strengthens our spirits, enabling us to endure hardships and resist compromise. Bickle also addresses the early church's struggle against the heresy that denied Jesus' divinity, affirming that He is both fully God and fully man, uniquely positioned to redeem humanity. The sermon calls believers to deepen their relationship with Jesus, recognizing His worthiness and the profound implications of His exaltation as the King of kings.