Reference

Mark 10:35-45 James and John request to sit at Jesus' side in his glory
"We are able" (and other Christian bumper stickers)

Be wary of the phrase "God has a plan." We are not pieces on God's cosmic chessboard. God's "plan" is to partner with us to redeem and recreate the world. The tools God uses are the sacraments and our spiritual gifts. As disciples, we can answer, "We are able" only with the understanding that we don't yet know where/how God is calling or how/when the spiritual gifts God has given us will be developed.