"You shall rise before the gray headed and honor the presence of an old man, and fear your God: I am the Lord" (Leviticus 19:32).
Growing old is natural. The old were once young, and the young will become old. These things are too self-evident to warrant comment. Today's command from the Law of Moses trained Israel to have respect for the elderly. But more than that, showing respect toward the aged is described as growing out of one's fear of God. He is "Lord" (YHWH, Jehovah), the eternally-existing one. Ultimately, we do not have power over the aging process, He does. Being disrespectful toward an older person reflects a fundamental failure to respect God, who gives life (both young and old). So, when you come upon an older person in the grocery store who can no longer push the shopping cart as quickly as you, don't become frustrated. When the older person is driving slower than you think he should, be patient. The "old man" should not be discounted because of his age, any more than the strength of the youth should be discounted by the aged. There is a place in this world for both. "The glory of young men is their strength, and the splendor of old men is their gray head" (Proverbs 20:29). Whether young or old, we must fear God because He is timeless.