The answer is: To lean on in old age

Zec 8:4

Zechariah’s proclamation about the future of Jerusalem paints a vibrant picture of hope and renewal. When people are seen leaning on staffs in their old age, it symbolizes strong roots – a reliance on community, stability, and the warmth that safety brings. Picture a bustling city where the elderly can finally step out of the shadows of fear instilled by invasions and turmoil. It’s a gentle reminder that everyone can enjoy a peaceful retirement surrounded by their family, which reflects the divine promise of security and joy.

Interestingly, references to the elderly leaning on staffs aren’t just in Zechariah. In Psalm 71:9, it speaks about the elderly not being cast away in their old age, emphasizing the dignity and worth in every life stage. Staffs have rich significance throughout the Bible, as they're often seen as symbols of comfort and support. Another key point of trivia: remember Moses—he had a staff, too! It became a tool of divine power and guidance, transforming from a simple stick to a powerful instrument energizing his mission.

Lastly, Zechariah’s vision of people resting under their vine and fig tree (Zec 3:10) also encapsulates this feeling of everyday comfort, blending community life with divine provision – an imagery continuation threading through the Bible, highlighting God's consistent tenderness in planning for His people's welfare throughout time.