寶刀未老

1. • treasure knife does not age (idiom) old but still vigorous

Character by character

• 寶(bǎo)jewel
• 刀(dāo)surname Dao
• 未(wèi)not yet
• 老(lǎo)prefix used before the surname of a person or a numeral indicating the order of birth of the children in a family or to indicate affection or familiarity