2 Kings 11:6
And a third part shall be at the gate of Sur; and a third part at the gate behind the guard: so shall ye keep the watch of the house, that it be not broken down. And a third part shall be at the gate of Sur; and a third part at the gate behind the guard: so shall ye keep the watch of the house, that it be not broken down.
The verse belongs to Jehoiada's plan to protect Joash and guard the house of the Lord as Athaliah's rule ended, after the infant Joash had been hidden in the temple until he could be placed on the throne following Athaliah's overthrow. It stations one third of the guard at the gate of Sur and one third at the gate behind the guard during Joash's public restoration and presentation as king, to keep the watch of the royal house and temple so that it would not be broken down or breached by anyone.
Those given this responsibility were Levites assigned to guard the Lord's house and protect it from being breached, and they could carry weapons for its defense. The arrangement kept the soldiers whose usual watch had ended on duty in the house of the Lord instead of sending them to their quarters, while the incoming guard was stationed at the designated posts. This change was made on the Sabbath, when it could be carried out more successfully.
The passage is an incidental reference to the Sabbath at Jehoash's accession to the throne of Judah around 778 B.C. It shows that the temple guards were changed on the Sabbath, which is taken as evidence that Sabbath observance was recognized in Israel.