The Messenger of Allah ﷺ is Allah's servant and His Messenger.
Affirming servanthood and messengership establishes two truths together: servanthood excludes divinity, while messengership establishes the sublime rank of prophethood, above the rank of ordinary saints.
Neither devotion should turn a prophet into God or God's son, nor should deficiency reduce the prophet to the rank of an ordinary saint. The balanced position affirms both his servanthood and the lofty station of his mission.