1 Kings 11:13

but will give one tribe The reference is to the tribe of Judah from which the southern kingdom took its name. Benjamin which went with Judah was so small as to be hardly worth accounting of, and Simeon was also absorbed in Judah. The same form of words is used below (1 Kings 11:32) in the account of Ahijah's action, though it is expressly said in a previous verse -Take thee ten pieces." One reason for the close union of Benjamin with Judah was that the territorial division between the two tribes was such as to make the Temple the common property of both. The city of the Jebusite, which David conquered, and all the ground north of the valley of Hinnom was in the tribe of Benjamin.

for Jerusalem's sake, which I have chosen In Deuteronomy 12:5 it is signified that God will choose some place out of all the tribes -to place His name there," and in 1 Kings 14:21 Jerusalem is expressly called -the city which the Lord did choose out of all the tribes of Israel to put His name there." Hence the place was an object of Jehovah's unchanging regard.