3 Nephi 20

The Savior said to the people in the Americas -

"Ye remember that I spake unto you, and said that when the words of Isaiah should be fulfilled—behold they are written, ye have them before you, therefore search them—
12  And verily, verily, I say unto you, that when they shall be fulfilled then is the fulfilling of the covenant which the Father hath made unto his people, O house of Israel."  (Book of Mormon | 3 Nephi 20:11 - 12)

Suggesting the that Isaiah wrote much of the covenants the Father made with the house of Israel.  I significant part of this covenant is that -

"I will gather my people together as a man gathereth his sheaves into the floor."  (Book of Mormon | 3 Nephi 20:18)

A greater understanding comes of this gathering as the Savior explained -

"And then shall the remnants, which shall be scattered abroad upon the face of the earth, be gathered in from the east and from the west, and from the south and from the north; and they shall be brought to the knowledge of the Lord their God, who hath redeemed them."  (Book of Mormon | 3 Nephi 20:13)

This gathering that the Lord did covenant with His people would be more of a spiritual gathering in that they will be gathered as sheaves to the knowledge of the Lord and be redeemed.  I personally consider the "house of Israel" will be the eternal family or house in the Celestial Kingdom