Peter quotes the prophet Isaiah to remind us of a harsh reality: "'People are like grass; their beauty is like a flower in the field. The grass withers and the flower fades, but the word of the Lord remains forever. And that word is the Good News that was preached to you.'" - 1 Peter 1:24-25 New Living Translation (NLT)
Human pride, achievements, social standing, and physical strength are all temporary. If we build our identity on these things, we will constantly live in anxiety because we know they are fading.
When the world feels like it's shifting under our feet, the gospel is the only ground that stays level. God's word has survived every attempt to destroy it and will continue to endure forever. This is where we must anchor our identity and hope.