'New Song' in the Bible

And they sing a new song, saying, Worthy art thou to take the book, and to open the seals thereof: for thou was slain, and didst purchase unto God with thy blood men of every tribe, and tongue, and people, and nation,

and they sing as it were a new song before the throne, and before the four living creatures and the elders: and no man could learn the song save the hundred and forty and four thousand, even they that had been purchased out of the earth.