الآية رقم (17) - فَمَهِّلِ الْكَافِرِينَ أَمْهِلْهُمْ رُوَيْدًا

(17) - (So allow time for the disbelievers. Leave them awhile. (17))

Allah (swt) tells His Messenger to go easy on the disbelievers for a little while, because if Allah (swt) had willed he would have done it directly but Allah (swt) had willed to allow time for them to achieve testing, then those who have strong faith would be able to bear the difficulties.

And if we read history, we find this delay did not prolong, but it was to cultivate faith and to teach how to be patient towards adversity, and soon victory of Allah (swt) came and the conditions of the world changed with this Muhammadan mission, so the light spread throughout the land and falsehood has departed.