Locke notes that, despite its importance, there is no need for the legislature to always be in session. It is not necessary to have a constant flow of new laws, and, in fact, a perpetually active legislature carries risks of abuse, as discussed in the last section. So the legislature, as a body or an individual, only needs to be "active" or "in session" at certain times, and is not perpetual.
The executive, on the other hand, must always be active, because the laws that the legislature passes must always be enforced. For this practical reason, as well as theoretical reasons discussed later, the executive and legislative powers should be separated.
Locke then moves on to discuss the international character of his civil state. All of the individuals forming the civil state and their government come together to form a single body, and this body is in a state of nature with respect to other states; in other words, international relations are governed by natural law. Locke names this the federative power, the natural power in charge of the state's international relations, and notes that it is often conjoined with the executive power, which manages the society within.
Chapter 13 begins with a reminder that, despite the high powers of the legislature, the people are still supreme over all, and have the power to "remove or alter the legislation" as they deem best. The community is always the true supreme power.
Within the government itself, however, the legislature always stands supreme. Locke notes that, even in a monarchy when the executive is vested in a single person who may also have some say in the legislature, this person only has supreme execution, not supreme control of the government.
Locke notes that the executive's power over the legislature does not imply that it controls the legislature. First, if the executive impedes the meeting and acting of the legislative when it is required, this constitutes an act of war against the people, since they have a right to the protection and work of that body when the state requires it. This control of the executive over the legislative, then, is a necessary trust placed in the executive: the legislative cannot meet constantly and the executive presides in its absence.