Related from Ibn Juraij who said: Someone I trust told me that ‘Umar, while he was making the rounds, heard a woman declaiming:
"The night has grown long and its margins dark
It keeps me awake with no beloved to play with
Were it not for fear of Allah, who has no equal
The sides of this bed would shake"
And ‘Umar said: What is with you? She said: You sent my husband away some months ago, and I have longed for him. He said: Are you thinking of doing something bad? She said: I seek refuge in Allah. He said: Then control yourself, for indeed all it takes is a message to him. And he sent for the man. Then he went in to see Hafsah [his daughter] and said: Truly I need to ask you about an issue that has troubled me, so dispel it from me; how long can a woman miss her husband? She lowered her head and was ashamed. He said: Indeed Allah is not ashamed of the truth. And with her hand she indicated three months or, at most, four. So ‘Umar prescribed that troops not be retained for more than four months"