“Remember, however, before all else, to strip things of all that disturbs and confuses, and to see what each is at bottom; you will then comprehend that they contain nothing fearful except the actual fear.”
Alternate translation: You will understand that there is nothing dreadful in this except fear itself. (translator unknown).
Source: Epistulae Morales ad Lucilium (Moral Letters to Lucilius), Line 12
Original
Illud autem ante omnia memento, demere rebus tumultum ac videre quid in quaque re sit: scies nihil esse in istis terribile nisi ipsum timorem.
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Seneca the Younger 225
Roman Stoic philosopher, statesman, and dramatist -4–65 BCRelated quotes

On Truth and Lie in an Extra-Moral Sense (1873)
Context: We produce these representations in and from ourselves with the same necessity with which the spider spins. If we are forced to comprehend all things only under these forms, then it ceases to be amazing that in all things we actually comprehend nothing but these forms. For they must all bear within themselves the laws of number, and it is precisely number which is most astonishing in things. All that conformity to law, which impresses us so much in the movement of the stars and in chemical processes, coincides at bottom with those properties which we bring to things. Thus it is we who impress ourselves in this way

“There is nothing to fear except fear it's self.”

“Henceforth the majesty of God revere;
Fear Him, and you have nothing else to fear.”
Answer to a Gentleman who apologized to the Author for Swearing. Compare: "Je crains Dieu, cher Abner, et n'ai point d'autre crainte" (translated: "I fear God, dear Abner, and I have no other fear"), Jean Racine, Athalie, act i. sc. 1 (1639–1699); "From Piety, whose soul sincere/ Fears God, and knows no other fear", W. Smyth, Ode for the Installation of the Duke of Gloucester as Chancellor of Cambridge.

Journal entry (14 October 1922), published in The Journal of Katherine Mansfield (1927)

“You see what power is – holding someone else's fear in your hand and showing it to them.”
Source: The Kitchen God's Wife (1991), p. 387