Expectancy or Urgency ?

"And whatever the Messenger gives you, take it, and whatever he forbids you, leave it. And fear Allah: truly Allah is severe in punishment. " [Qur'an 59:7

Expectancy or Urgency. Both are the acts of anticipating the unknown. The big unknown of accepting what He gives and leave what He forbids. But we are at most gulity of taking what He forbids.Though, when say we fear Him, the Almighty. Why?