porter was astonished to see strang announce to his followers that he had unearthed a set of brass plates from beneath an oak tree just outside of pontoosuc , north of nauvoo : the angel of the lord came unto me , james , on the first day of september , in the year eighteen hundred and forty-four , and the light shined about him above the brightness of the sun , and he showed unto me the plates of the sealed record , and he gave into my hands the urim and thummim .