In this chapter John makes reference about the vision of the persecution which transforms abruptly into a vision of the church in glory
The one hundred and forty four thousand symbolize all the faithful saints, the mount of sion represents a spiritual reality that expresses the communion of the saints, not a geographical place, the name of the father contrasts deliberately with the name of the beast
Likewise the one hundred and forty-four represent the remnant of sealed Jews and consequently exempted from going through the great tribulation, they will be very identified with the lamb (Jesus Christ) and Mount Zion, typical of the seat of power of the kingdom in Jerusalem.
The new song is a song of redemption, which only the redeemed can understand, they are spiritual virgins who have remained faithful to the Lord, not having prostituted themselves through idolatry, they are without stains, free of guilt because they are in Christ and are, Therefore, an acceptable sacrifice