Deuteronomy 18:14
For these nations, which thou shalt possess, hearkened unto observers of times, and unto diviners: but as for thee, the LORD thy God hath not suffered thee so to do. For these nations, which thou shalt possess, hearkened unto observers of times, and unto diviners: but as for thee, the LORD thy God hath not suffered thee so to do.
The command sets Israel apart from the nations whose territory they were to possess by forbidding them to copy their heathen customs. Those nations listened to observers of times and to diviners, but that practice of divination and superstition was not allowed for God's people. The prohibition is absolute: what was customary among the peoples to be dispossessed was not to become customary in Israel. In place of such forbidden inquiry, God Himself would reveal His will through prophets of His own appointing. Because that divinely appointed channel was provided, Israel had no need and no excuse to consult diviners or soothsayers.