阳奉阴违

yángfèng-yīnwéi

[overtly agree, but covertly oppose; out wardly obey but inwardly oppose] 当众同意背后反对

如有日与胥徒比, 而阳奉阴违, 名去实存者, 断以白简随其后。 --《明臣奏议·革大户行召募疏》