In Spurgeon's devotional, "The Magnitude of Grace," he emphasizes the sufficiency of God's grace and the importance of relying on His strength in our weakness. He argues that our own strength is insignificant compared to God's power, and that we should be grateful for the trials and tribulations that drive us to seek His strength.

Spurgeon draws on Paul's words in 2 Corinthians 12:9, where Paul declares, "My grace is sufficient for thee: for my strength is made perfect in weakness." Spurgeon interprets this verse to mean that God's grace is not limited by our own strength or abilities. Rather, it is in our weakness that God's strength is most fully revealed.

Spurgeon uses several metaphors to illustrate this point. He compares God's grace to the vastness of the sky for the bird and the ocean for the fish. He also compares the believer to a "worm" who is able to "thresh the mountains" when empowered by God's strength.

The central message of Spurgeon's devotional is one of encouragement and hope. He reminds us that no matter how weak or insignificant we may feel, God's grace is sufficient for us. He is able to give us the strength we need to overcome any obstacle.

Here are some key points from Spurgeon's devotional: