Oh wow, blimey!! I had heard of a story of a family that was saved from Sodom but hadn't heard that bit! Did God ask him to do it, or did he do it on his own back?
It's in Genesis 19. This happens to be one of the chapters that has been modified by the Joseph Smith translation. I'll post the KJV first then the JST. Take from them what you will.
KJV
1 And there came a
two b
angels to Sodom at even; and
Lot sat in the gate of Sodom: and
Lot seeing
them rose up to meet them; and he bowed himself with his face toward the ground;
2 And he said, Behold now, my lords, turn in, I pray you, into your servants house, and tarry all night, and a
wash your feet, and ye shall rise up early, and go on your ways. And they said, Nay; but we will abide in the street all night.
3 And he pressed upon them greatly; and they turned in unto him, and entered into his house; and he made them a a
feast, and did bake b
unleavened bread, and they did eat.
4 ¶ But before they lay down, the men of the city,
even the men of Sodom, compassed the house round, both old and young, all the people from every quarter:
5 And they called unto
Lot, and said unto him, Where
are the men which came in to thee this night? bring them out unto us, that we may a
know them.
6 And
Lot went out at the door unto them, and shut the door after him,
7 And said, I pray you, brethren, do not so wickedly.
8 a
Behold now, I have two b
daughters which have not known man; let me, I pray you, bring them out unto you, and do ye to them as
is good in your eyes: only unto these men do nothing; for therefore c
came they under the shadow of my roof.
9 And they said, Stand back. And they said
again, This one
fellow came in to a
sojourn, and he will needs be a judge: now will we deal worse with thee, than with them. And they pressed sore upon the man,
even Lot, and came near to break the door.
10 But the men put forth their hand, and pulled
Lot into the house to them, and shut to the door.
11 And they smote the men that
were at the door of the house with a
blindness, both small and great: so that they wearied themselves to find the door.
12 ¶ And a
the men said unto
Lot, Hast thou here any besides? son in law, and thy sons, and thy daughters, and whatsoever thou hast in the city, b
bring them out of this place:
13 For we will destroy this place, because the a
cry of them is waxen great before the face of the Lord; and the Lord hath sent us to destroy it.
14 And
Lot went out, and spake unto his sons in law, which married his daughters, and said, Up, a
get you b
out of this place; for the Lord will destroy this city. But he seemed as one that c
mocked unto his sons in law.
JST
Verses 1-7 are the same...then:
9
And they said unto him, Stand back. And they were angry with him. 10
And they said among themselves, This one man came in to sojourn among us, and he will needs now make himself to be a judge; now we will deal worse with him than with them.
11
Wherefore they said unto the man, We will have the men, and thy daughters also; and we will do with them as seemeth us good.
12
Now this was after the wickedness of Sodom.
13 And
Lot said, Behold now, I have two daughters which have not known man; let me, I pray you,
plead with my brethren that I may not bring them out unto you; and ye shall
not do unto them as seemeth good in your eyes;
14
For God will not justify his servant in this thing; wherefore, let me plead with my brethren, this once only, that unto these men ye do nothing,
that they may have peace in my house; for therefore came they under the shadow of my roof.
15
And they were angry with Lot and came near to break the door, but the
angels of God, which were holy men, put forth their hand and pulled
Lot into the house unto them, and shut the door.