The Prophet (sallallaahu alayhe wa sallam) passed by an Ansari man who was counseling his brother on modesty (he was advising him not to be too much shy or modest).
The Prophet said: "Leave him (and do not advise him like this); for modesty is part of faith." (Bukhari and Muslim).
The Prophet, sallallaahu alayhe wa sallam, also said, "Modesty results in good alone and nothing else." (Bukhari and Muslim).