Chapter 7 is a continuation of the second perspective from which John tells of Christ's victory, which began in chapter four. So far we've seen the Lion/Lamb as the only worthy one to open the seals on God's scroll (signifying Christ as the one who brings God's will to completion). We read about how all things, even the things caused by sin (which God doesn't cause, but does allow), are going exactly according to God's plan.
In chapter 7, this second perspective comes to an end, once again with the Lamb victoriously "at the center of the throne (v17)" surrounded by His saints and angels.
v1-3 - The angels are standing reading to bring all things to an end, but no harm will come until all of God's saints are sealed.
v4-8 - The 144k are sealed, a number not meant to be taken literally, but the perfect factor of 12, representing the full number of God's elect from the 12 tribes of Israel.
v9-12 - The 144k from Israel are not the only ones sealed unto redemption. An uncountable throng from all over the globe is included as well.
v13-14 - Another representation of what it will be like for those redeemed and sealed in Christ, who will never hunger or suffer again, praising God and the Lamb who are at the center of the throne.
Many people today are basing their core identity in external factors, such as race, nationality, gender, and sexual orientation. These constructs have constantly shifting definitions that no longer reflect any sort of absolute truth, often each segment tries to present itself as more victimized than the others. The result of this is a society which has become more and more fractured, polarized and isolated.