24Then Jesus told his disciples, “If anyone would come after me, let him deny himself and take up his cross and follow me. 25For whoever would save his life will lose it, but whoever loses his life for my sake will find it.
This expression “to take up one’s cross” is not an idiom by which to refer to some trivial annoyance–an ingrown toenail, perhaps, or a toothache, or an awkward in-law: “We all have our crosses to bear.” No, in the first century it was culturally unthinkable to make jokes about crucifixion as it would be today to make jokes about Auschwitz. To take up your cross does not mean to move forward with courage despite the fact you lost your job or your spouse. It means you are under sentence of death; you are taking up the horizontal cross-member on your way to the place of crucifixion. You have abandoned all hope of life in this world. And then, Jesus says, and only then, are we ready to follow him.
— D.A. Carson in Scandalous: The Cross and Resurrection of Jesus.