"And if they used to say," meaning: [and if the people of Mecca used to say before Muhammad (peace be upon him) was sent].
﴿وَإِن كَانُوا ليقولون﴾ يَعْنِي [وَإِن كَانَ أهل مَكَّة ليقولون قبل أَن يبْعَث محمدٌ ﷺ]
