Do you not know that your bodies are temples of the Holy Spirit, who is in you, whom you have received from God? You are not your own; you were bought at a price. Therefore honor God with your bodies. ~ 1 Corinthians 6: 19-20
Serving others takes physical strength and stamina. Loving others comes in many forms and often asks us to exhaust ourselves for the ones we care about.
Take care of your body, your asset -- for it is the temple of Christ and houses the Holy Spirit. Your physical health helps you leverage your strength to serve others.
GO DEEPER: Romans 12: 1-5