From Halopedia, the Halo wiki
In March 2553, while preparing for his assault on Vadam, Avu Med 'Telcam ordered Olar to keep watch over Evan Phillips. At Evan's request, Olar provided him with clothing and allowed him to venture into the underground tunnels of the Temple of the Abiding Truth. After being informed that Kilo-Five would be coming for Phillips, 'Telcam ordered Olar to allow them to take him to avoid retaliation from Earth.
When Kilo-Five arrived at the temple's doorway, Olar informed them that Phillips had been gone for hours and that he could not leave his post to retrieve him. Olar initially refused them entry into the temple seeing as they were nonbelievers. As Black Box negotiated with him, a number of Sangheili outside debated whether they should kill humans on the holy ground. As the Sangheili crowd became aggravated, Olar relented and allowed Kilo-Five inside the temple, locking the doors as a precaution. Olar then gestured the way to the tunnels and told them not to touch anything inside the temple.
Olar was later seen arguing outside with the large crowd before they charged at Kilo-Five upon seeing them leave the temple.
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