Retirement.

Isaiah 46: 4

Even when you're old, I'll take care of you. Even when your hair turns gray, I'll support you and save you. 

Numbers 8: 24-26 

Men twenty-five years old or more shall come to take part in the work at the tent of meeting, but at the age of fifty, they must retire from their regular service and work no longer. They may assist their brothers in performing their duties at the tent of meeting, but they themselves must not do the work. 

Application:

God promises to be faithful and sovereign, even when you are old and gray! The Bible was written prior to our modern concept of retirement, but core principles remain the same. The second mentioned verse is God talking to Moses about the Levites. God says that once a person reaches a certain age, their roles in the community changes. God states that having gray hair is a 'crown of splendor'. Wouldn't you agree that verse implies he has a special place in his heart for people who are not in the workforce anymore?