Verses with the word offspring in the New Testament (3 verses):

Acts 17:28
For in him we live, and move, and have our being; as certain also of your own poets have said, For we are also his offspring.

Acts 17:29
Forasmuch then as we are the offspring of God, we ought not to think that the Godhead is like unto gold, or silver, or stone, graven by art and man's device.

Revelation 22:16
I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star.