Why is “يُنْفِقْ” jussive in “لِيُنْفِقْ ذُو سَعَةٍ”?

Inshāʾ: Requestive and Non-requestive Forms, Imperative Constructions and Rhetorical Functions

• Because dhū follows it
• Because a perfect verb precedes it
• Because it is an interpreted infinitive
• The lām of command governs the jussive