Arthashastra
अहि भयाद् अभ्यन्तरः कोपो बाह्य कोपात् पापीयान्, अन्तर् अमात्य कोपश् च अन्तः कोपात् ॥
Internal troubles are more serious than external troubles which are like the danger arising from a lurking snake. Troubles due to a minister are more serious than other kinds of internal troubles.
english translation
ahi bhayAd abhyantaraH kopo bAhya kopAt pApIyAn, antar amAtya kopaz ca antaH kopAt ॥
hk transliteration by Sanscript