(Ibid. 13) "All the native-born shall thus do, etc.": From here we learn that libations can be donated. How much? Three logs, (which suffice for a lamb). And whence is it derived that if he wishes to add he may do so?
From "shall do." I might think he can decrease; it is, therefore, written "thus." From here it was derived: One is not to donate two or five, (which do not [exactly] suffice for anything), but he may donate three or four or six or above, (which do [exactly] suffice for something). Variantly: What is the intent of "All the native-born, etc."?
Because it is written (Vayikra 22:25) "And from the hand of a gentile you shall not present (as a sacrifice) the bread of your G-d of all these (blemished animals)" — These you do not accept (from gentiles), but you do accept unblemished animals. After we have learned that a gentile may bring a burnt-offering, I can now conclude: An Israelite brings a burnt-offering and a gentile brings a burnt-offering.
Can I also conclude: Just as an Israelite brings libations, so, a gentile brings libations? It is, therefore, written "All the native-born shall thus do these (libations)" — An Israelite brings libations, but a gentile does not. I might, then, think that his burnt-offering does not require libations; it is, therefore, written "shall thus do" (to bring libations) — whence they ruled: If a gentile sent his burnt-offering from abroad and sent libations along with it, his own are used; and if not they are to be brought by the congregation.