How do we reconcile the condition of safety from harm for enjoining good and forbidding evil with Allah's saying: "They strive in the cause of Allah and do not fear the blame of a critic," and the Prophet's (PBUH) saying: "Let not the awe of people prevent a man from speaking the truth"?

There is nothing in the verse or Hadith that necessitates enjoining good while fearing death or harm. The verse speaks of not fearing people's blame and reproach, not of fearing for one's life from being killed. The Hadith, "Let not the awe of people prevent a man from speaking the truth when he knows it," does not indicate the obligation of enjoining good when there is a fear of harm. The command may be for resolution (encouragement) and not for obligation, especially since there is a consensus on the waiver of enjoining good in this situation, and it is permissible to utter words of disbelief under duress. As for awe due to slander and blame, it is not a deterrent, and this may be what is intended in the Hadith.