the pen is mightier than the sword

This phrasing due to Bulwer-Lytton 1839, in his play Richelieu; Or the Conspiracy:

Beneath the rule of men entirely great,

The pen is mightier than the sword.

The sentiment is traditional, and has many antecedents; see Wikipedia. Some examples:

• Cicero, De Officiis I.lxxvii: cēdant arma togae (“arms yield to persuasion”).
• Antonio de Guevara, 1529, Reloj de príncipes, compares the pen to the lance; translated into English by Thomas North, 1557, as Diall of Princes.
• William Shakespeare, 1600, Hamlet, Act 2, scene II, " […] many wearing rapiers are afraid of goosequills."

the pen is mightier than the sword

1. (idiomatic) More influence and power can be usurped by writing than by fighting.

• actions speak louder than words

• the tongue wounds more than a lance