A man bore witness to ‘Umar Ibn Al-Khattaab so ‘Umar said to him: “I do not know you, but it does not matter that I do not know you. Bring me someone who does know you.”
A man among the peole said: “I know him.” ‘Umar asked: “What do you know about him?” He said: “He is of good character and is virtuous.”
‘Umar asked: “Is he your neighbour who you know by night and by day, and you know when he comes in and goes out?” The man said: “No.”
‘Umar asked: “Did h have any financial dealings with you which is the way to know whether he is God-fearing or not?” The man said: “No.”
‘Umar then asked: “Has he been your companion on a journey, which is the best way to know whether he is of noble character and attitude?” The man said: “No.”
So ‘Umar said: “Then you do not know him.”
[Sunan Al-Bayhaqi, 10/125 & Mawsoo’ah Fiqh ‘Umar, p. 731]
The Authentic Base 