Because there came to him the blind man (i.e. 'Abdullah bin Umm-Maktum, who came to the Prophet (Peace be upon him) while he was preaching to one or some of the Quraish chiefs).
Such will be the Kafarah (disbelievers in Allah, in His Oneness, and in His Messenger Muhammad (Peace be upon him), etc.), the Fajarah (wicked evil doers).
IMPORTANT: All Scripture text has context and background. Scripture should never be read literally or in isolation. Always seek clarification from religious scholars and teachers. In general, Scripture adheres to four principles: (1) Literal Meaning - What the Scripture says (2) Historical Setting - The story events; how the Scripture was understood in its time (3) Grammar - The surrounding sentence and paragraph; textual context (4) Synthesis - A comparison with similar Scripture to give a better contextual understanding