messenger We sent was only that he should be obeyed by Allah’s permission; and had they, when they wronged themselves, come to you, sought Allah’s forgiveness, and the Messenger had prayed for their forgiveness, they would surely have found Allah Ever-Relenting, Most Merciful.”
This verse contains Allah’s oath by His lordship over Muhammad—peace and blessings be upon him—an oath that points to the special concern He has shown His Prophet, for the lordship mentioned here is a particular lordship.
Allah, exalted is He, exercises two kinds of lordship over His creation. The first is universal, extended to everyone, as in His words, “All praise belongs to Allah, Lord of all creation” (al-Fātiḥah 1:2). The second is particular, reserved for those servants He singles out, as in the present verse: “But no, by your Lord, they will not believe until they make you judge concerning whatever has arisen between them.” Both kinds appear together in His statement about Pharaoh’s sorcerers: “They said, ‘We believe in the Lord of all creation, the Lord of Moses and Aaron’” (al-Aʿrāf 7:122). “Lord of all creation” indicates universal lordship, whereas “Lord of Moses and Aaron” indicates the particular.
Particular lordship entails a special care from Allah, exalted be He. Thus He swore—glorified and praised be He—by His lordship over His servant Muhammad with an emphatic oath introduced by the negative particle lā in His saying, “But no (fa-lā), by your Lord.” This lā is for emphasis; had He said, “So, by your Lord, they will not believe,” the sentence would still be complete, yet He inserted lā to heighten the force of the oath, just as in His words, “No indeed, I swear by the Day of Resurrection” (al-Qiyāmah 75:1). The intention is not to deny the swearing itself—as though Allah does not swear by the Day of Resurrection—but to stress and reinforce the oath. Here, then, lā functions as reinforcement and admonition.
“But no, by your Lord, they will not believe until they make you judge concerning whatever has arisen between them”—that is, until they appoint you as arbiter in the disputes that have arisen among them. The verb shajara refers to what has erupted in the way of contention. “Until they make you judge” means that they must make you yourself the judge in whatever disagreements arise among them, whether in matters of religion or matters of this world.