Go and ask believers now, and I think many will tell you: “Oh that I could live my young days over again!” He will most likely say, “Oh that I had spent the beginning of my life in a better way! Oh that I had not laid the foundation of evil habits so strongly in the springtime of my journey!”
Young men, I want to save you all this sorrow, if I can. Hell itself is truth known too late. Be wise in time. What youth sows, old age must reap. Do not give the most precious season of your life to that which will not comfort you in the latter days of your life. Sow to yourselves rather in righteousness: break up your hard ground, don’t sow among thorns.
-- J.C. Ryle