Translation:

67. O Apostle! proclaim the (Message) which hath been sent to thee from thy Lord. If thou didst not thou wouldst not have fulfilled and proclaimed His mission: and Allah will defend thee from men (who mean mischief). For Allah guideth not those who reject faith.

Notes (Tafseer)

777. Muhammad had many difficulties to contend with, many enemies and dangers to avoid. Hismission must be fulfilled. And he must-as he did-go forward and proclaim that Message and fulfil his mission, trusting to Allah for protection, and unconcerned if people who had lost all sense of right rejected it or threatened him.