He who knows only how to wield a pen usually feels quite helpless in the face of practical problems.

光会耍笔杆的人，碰到实际问题往往束手无策。

《新英汉大辞典》

If doctors wield the pen, why do they do it so differently from one place to another?

NEWYORKER: The Cost Conundrum

Someone or something is using me to untangle the tangled plot over whose direction I have as little influence as the pen has over the poets who wield it, or man over the gods who manipulate him, or the knife over the murderer.

NPR: Excerpt: 'Borges and the Eternal Orangutans'

It is in those circumstances that you may wish to wield a pen, to reflect upon and write the story of your experiences.

CNN: The importance of belonging