“During his illness, Lenin repeatedly addressed letters and proposals to the leading bodies and congresses of the party. It must be definitely stated that all these letters and suggestions were invariably delivered to their destination and they were all brought to the knowledge of the delegates to the Twelfth and Thirteenth Congresses, and have invariably exercised their influence on the decisions of the party. If all of these letters have not been published, it is because their author did not intend them to be published. Comrade Lenin has not left any “Testament”; the character of his relations to the party, and the character of the party itself, preclude the possibility of such a “Testament.” The bourgeois and Menshevik press generally understand under the designation of “Testament” one of Comrade Lenin’s letters (which is so much altered as to be almost unrecognizable) in which he gives the party some organizational advice. The Thirteenth Party Congress devoted the greatest attention to this and to the other letters, and drew the appropriate conclusions. All talk with regard to a concealed or mutilated “Testament” is nothing but a despicable lie, directed against the real will of Comrade Lenin and against the interests of the party created by him.”

https://www.marxists.org/archive/trotsky/1925/07/lenin.htm,Letter on Max Eastman's Book, July 1, 1925