What effect can fronting ʿan ṣalātihim have?

Supplementary Practice 21: Comparative Rhetorical Study of Sūrat Quraysh and al-Māʿūn

• Assume all fronting necessarily establishes exclusivity
• Make ʿan stand for an omitted past-tense verb
• It makes prayer immediately prominent as the object of negligence
• Deny any salience created by the fronted complement