Diligenza
Italian performance direction: con diligenza means "with diligence," calling for a careful, precise execution.
What it means
Diligenza is the Italian word for diligence and care. As a performance direction it usually appears in the phrase con diligenza, "with diligence," and calls for an especially careful, precise execution, without directly prescribing tempo or dynamics. The instruction is aimed not at the sound itself but at the performer's care in executing it.
Musical use
Character markings of this kind, drawn from the Italian vocabulary of performance directions, are found mainly in older instrumental music, where they describe the desired manner of execution alongside tempo and dynamic markings. Con diligenza is close in meaning to terms such as carefully or precisely executed, and is distinct from purely tempo-related markings, which concern speed rather than care of execution.
Performance practice
Understand con diligenza as a call for particular accuracy: pay attention to clean articulation, precise rhythm, and exact intonation rather than playing the passage casually. The marking says nothing about tempo, so read it together with the piece's other performance directions.