व्यवस्थितः प्रशांतात्मा कुपितोऽप्यभयंकरः ।
अव्यवस्थितचित्तस्य प्रसादोऽपि भयंकरः ॥
vyavasthitaH prashAntAtma kupito api abhayankaraH ।
avyavasthita chittasya prasAdo api bhayankaraH ॥
When a usually calm and collected person gets angry - it is still not that fearsome. One can expect him to be rational and control his anger. But if one sees inconsistent fellow bestow favors, he must get worried. Because such people could turn around any time and hurt you.