It is made clear that as the tribulation progresses, the family that is being saved is the family of God, the family of believers. It is the family bound by the blood of the Lord, not necessarily the blood of the flesh (thought those who are related by flesh may be saved). It would also seem that this includes the Angels (the elect of heaven) since they will be gathered â€œfrom the farthest end of the earth to the farthest end of heavenâ€ (verse 27).
In verse 10 we have â€œThe gospel must first be preached to all the nations.â€ Does this imply, as some propose, that every person in every nation must hear the Gospel? Since â€˜allâ€™ is used in many places in the New Testament to indicate not every single person but a reasonable number from some group (eg. â€˜all of the city came outâ€™ does not mean every single person but a large representation), then the answer is no. It does seem to indicate, however, that the Gospel will reach every nation at some level. Since one must assume that they would hear it from the body of believers, this indicates that evangelism and missions continue to hold a significant ongoing role in the lead up to the end.
In verses 8, 12 and 13, among others, it is clearly stated that the peoples will be divided at every level of society, even within the nuclear family. When this is followed by â€œthe elect, whom He choseâ€ in verse 20 indicating those who would were appointed to salvation, it is clear that election crosses every boundary of human society and relationship.
Further, since this choice by the Lord was accomplished before the creation was put in place (â€He chose us in Him before the foundation of the worldâ€ Ephesians 1:4), it must be unrelated to any human factor of either individual merit or demerit, or of human relationships, as shown in the divisions discussed above.
So, there we have it in a microcosm – all of Him, according to His original plan alone, working towards His ends alone.
Soli Deo Gloria.