'Cutoff' in the Bible

See, then, the kindness and severity of God: severity upon those who have fallen, but upon you the kindness of God--if you continue in his kindness, for otherwise you also will be cut off.

For if you were cut off from what is by nature a wild olive tree, and contrary to nature were grafted into a cultivated olive tree, how much more will these who are {natural branches} be grafted into their own olive tree?