Until it became

1. Alma 15: 3
     3 And also Zeezrom lay sick at Sidom, with a burning fever, which was caused by the great tribulations of his mind on account of his wickedness, for he supposed that Alma and Amulek were no more; and he supposed that they had been slain because of his iniquity. And this great sin, and his many other sins, did harrow up his mind until it did become exceedingly sore, having no deliverance; therefore he began to be scorched with a burning heat.
2. Alma 55: 33
     33 And now it came to pass that it was expedient for Moroni to make preparations to attack the city Morianton; for behold, the Lamanites had, by their labors, fortified the city Morianton until it had become an exceeding stronghold.