The ability to print material is very beneficial for the world, because with it Torah can increase and spread. Now, since in general Torah scholars cannot afford to print their sefarim (books), it is proper for the more affluent members of the nation of Avraham to give generously to authors of Torah works. In this way, they share the reward of the Sage, as the verse says: To sit in the shelter of wisdom is to sit in the shelter of money (Koheles 7:12). It all depends on the importance of the work; how much it is needed by the public and how much it affects the service of Hashem, may He be blessed.
When we reflect on this matter, we see that there is hardly any other mitzvah that can be done with money, for the effects of other mitzvahs that can be done with money last only for a limited amount of time. The mitzvah begins and ends. But when a person gives money to publish a holy book, his righteous giving will stand for him for all future generations; he thereby gives merit to the many [who will now have the opportunity to study the book] and so the merit of the many are a credit to him. How fortunate he is and how good is his lot! With such giving he acquires a good name, words of Torah and life in the World to Come. Even in this world he will be blessed that his wealth will increase.