1 Samuel 14:3
And Ahiah, the son of Ahitub, I-chabod’s brother, the son of Phinehas, the son of Eli, the LORD’s priest in Shiloh, wearing an ephod. And the people knew not that Jonathan was gone. And Ahiah, the son of Ahitub, I-chabod’s brother, the son of Phinehas, the son of Eli, the LORD’s priest in Shiloh, wearing an ephod. And the people knew not that Jonathan was gone.
Ahiah, the son of Ahitub and brother of Ichabod, was the grandson of Phinehas and great-grandson of Eli, serving as the Lord's priest at Shiloh and wearing an ephod while stationed with the Israelite force, so both the priest and the ark form part of the setting for Jonathan's attack on the Philistines. The declaration that the people did not know Jonathan was gone means his assault on the Philistine camp and garrison began in secret, without the knowledge of the army.
Saul and his men became aware of what Jonathan had done only after the battle was already underway, when Jonathan and his armor-bearer were found to be absent and reported missing. Once he learned they were missing, Saul ordered the ark to be brought forward and directed the priest to inquire of God, but the increasing tumult of the battle cut the inquiry short.
Saul called for the ark and its attending priests, including Ahiah, although he knew the history of Israel's defeat when Hophni and Phinehas had carried the ark into battle, and he did so in hope of reviving the courage of the people and reinforcing his own authority.