"So to that," because they doubted it and were suspicious of Islam and the Quran, "invite, and remain on a right course as you are commanded," regarding Islam.
﴿فَلِذَلِكَ﴾ لما شكوا فِيهِ وارتابوا من الْإِسْلَام وَالْقُرْآن ﴿فَادْعُ وَاسْتَقِمْ كَمَا أُمِرْتَ﴾ على الْإِسْلَام.
