"We are the Reason" is a classic Christian contemporary song that connects the celebration of Christmas with the sacrifice of Easter.
The song is designed to shift the listener's perspective from the "easy" joy of Christmas (gifts, childhood wonder) to the difficult reality of the crucifixion.
It's a reflective song meant to evoke a sense of personal connection to the story. It tells the listener that the entire journey from the manger to the cross was motivated by love for them.