Revelation 14:3

3 They sang as it were a new song before the throne, before the four living creatures, and the elders; and no one could learn that song except the hundred and forty-four thousand who were redeemed from the earth.

A. The voices are here identified as coming from the 144,000. They sing a new song. It is a song that could not be sung before Christ came. Before the death of Christ, there was no redemption, no forgiveness, no salvation before the blood of Christ was shed on the cross.

B. In the previous verse this voice is singular (denoting its unity and unison) and now it is in the plural as 144,000 sing together.

C. Again, there is a parallel to the children of Israel. When they came out of great tribulation in Egypt, crossing the Red Sea, the first thing they did was sing a song of deliverance. So the church of the redeemed sings a new song of deliverance when they come out of the great tribulation of sin.

D. For those who have not obeyed the gospel, the song is not familiar. If one has not committed their life to Christ, the words are just a strange sound.