“Death only closes a Man's Reputation, and determines it as good or bad.”

21.
Every Good Man is Free

Source: The Gay Science

Source: Thebaid, Book X, Line 712

This is from a set of maxims which Washington copied out in his own hand as a school-boy: "Rules of Civility and Decent Behaviour in Company and Conversation http://gwpapers.virginia.edu/documents/the-rules-of-civility/" Rule # 56 written out by Washington ca. 1744:
: These maxims originated in the late sixteenth century in France and were popularly circulated during Washington's time. Washington wrote out a copy of the 110 Rules in his school book when he was about sixteen-years old... During the days before mere hero worship had given place to understanding and comprehension of the fineness of Washington's character, of his powerful influence among men, and of the epoch-making nature of the issues he so largely shaped, it was assumed that Washington himself composed the maxims, or at least that he compiled them. It is a satisfaction to find that his consideration for others, his respect for and deference to those deserving such treatment, his care of his own body and tongue, and even his reverence for his Maker, all were early inculcated in him by precepts which were the common practice in decent society the world over. These very maxims had been in use in France for a century and a half, and in England for a century, before they were set as a task for the schoolboy Washington.
:* Charles Moore in his Introduction to George Washington's Rules of Civility and Decent Behaviour in Company and Conversation (1926) http://gwpapers.virginia.edu/documents/civility/index.html, edited by Charles Moore, xi-xv
Misattributed

A Thousand & One Epigrams: Selected from the Writings of Elbert Hubbard (1911)

You're Only Human (Second Wind).
Song lyrics, Greatest Hits - Volume I & Volume II (1985)

As translated by William Scott Wilson. This first sentence of this passage was used as a military slogan during the early 20th century to encourage soldiers to throw themselves into battle. Variant translations:
Bushido is realised in the presence of death. In the case of having to choose between life and death you should choose death. There is no other reasoning. Move on with determination. To say dying without attaining ones aim is a foolish sacrifice of life is the flippant attitude of the sophisticates in the Kamigata area. In such a case it is difficult to make the right judgement. No one longs for death. We can speculate on whatever we like. But if we live without having attaining that aim, we are cowards. This is an important point and the correct path of the Samurai. When we calmly think of death morning and evening and are in despair, We are able to gain freedom in the way of the Samurai. Only then can we fulfil our duty without making mistakes in life.
By the Way of the warrior is meant death. The Way of the warrior is death. This means choosing death whenever there is a choice between life and death. It means nothing more than this. It means to see things through, being resolved.
I have found that the Way of the samurai is death. This means that when you are compelled to choose between life and death, you must quickly choose death.
The way of the Samurai is in death.
I have found the essence of Bushido: to die!
Hagakure (c. 1716)
Context: The Way of the Samurai is found in death. When it comes to either/or, there is only the quick choice of death. It is not particularly difficult. Be determined and advance. To say that dying without reaching one's aim is to die a dog's death is the frivolous way of sophisticates. When pressed with the choice of life or death, it is not necessary to gain one's aim.
We all want to live. And in large part we make our logic according to what we like. But not having attained our aim and continuing to live is cowardice. This is a thin dangerous line. To die without gaining one's aim is a dog's death and fanaticism. But there is no shame in this. This is the substance of the Way of the Samurai. If by setting one's heart right every morning and evening, one is able to live as though his body were already dead, he gains freedom in the Way. His whole life will be without blame, and he will succeed in his calling.

My Heart's in the Highlands (1939)