Anas bin Malik (May Allah be pleased with him) reported:
Messenger of Allah ﷺ said, "If a young man honours an older person on account of his age, Allah appoints someone to show reverence to him in his old age"

[At-Tirmidhi].

وعن أنس رضي الله عنه قال: قال رسول الله ﷺ :"ما أكرم شاب شيخًا لسنه إلى قيض الله له من يكرمه عند سنه" ((رواه الترمذي وقال: حديث غريب)).