The Bible teaches us that the best way for young people to secure their hearts is to fill them with God's Word. The Bible says in Psalm 119:11, "I have stored up your word in my heart, that I might not sin against you." Reading and studying God's Word is the best way to protect our hearts from sin. Additionally, young people can guard their hearts by surrounding themselves with godly friends and mentors who can encourage and challenge them to live a life of holiness and purity.