听其言观其行　

◎ 听其言观其行 tīng qí yán guān qí xíng

[listen to what a person says and watch what he does;take note of sb.‘s words but judge him by his deeds] 听一个人说什么,又看他做什么,常有“不仅要听他说的,更重要的是看其做的如何”的含义