यथा चित्तम् तथा वाचो यथा वाचस्तथा क्रिया: ।
चित्तम् वाचि क्रियायाम् च साधुनामेकरूपता ॥

yathā cittam tathā vāco yathā vācastathā kriyā: ।
cittam vāci kriyāyām ca sādhunāmekarūpatā ॥

What is in mind should be reflected in one's speech. What is in one's speech should be reflected in one's actions.
Thus the person whose mind, speech and actions are same is a 'sadhu'