i  believe jesus  is capable of anything...the physical healing of those days were due to the fact that he was  physically living among them...surely his power to heal was spiritual   from the father.

today we are guided by our faith....when in the past people belived because they saw jesus ,today we believe by our faith...so that faith is the presence of the holy spirit in us ....i think the physical healing of the past and the spiritual healing of the present are if not one and the same thing then they compliment each other.

Jesus didnt discourage them however he wanted to point out to them the degree of commitment they should have if they were planning to follow him.he pointed out that they have to leave everything behind and only live the life that God wanted them to live.he tells them the son of man has nowhere to lay his head ....Jesus didnt have any worldly possesions....

there is also  a hint to something else in this paragraph ,thats when Jesus tells them leave the dead to bury their own....pointing out to the fact that all are spiritually dead ....unless they follow Jesus/God