A sandstone sculpture of a kneeling man sharpening a knife could be a long forgotten work by Michelangelo, according to an Italian scholar who has rediscovered the statue in a private collection.

Measuring 111 centimeters (3.65 feet), the statue is now on display for the first time after more than 120 years at the exhibition, “And There Was Light. The Masters of the Renaissance,” in Göteborg, Sweden.

The powerful sculpture is a copy of a marble statue known as the “Arrotino” (the Blade-Sharpener) on display at the Uffizi gallery in Florence.

Representing the Scythian slave who served Apollo and flayed the satyr Marsyas, the Uffizi sculpture is itself a Roman copy from a lost Hellenistic original....