So… where are the miracles, signs and wonders that must accompany your direct calling by God, as verification? Jesus Himself submitted to this proof-test, so I wouldn’t be too quick to exempt yourself from this same test, unless of course you wish to say you are greater than Jesus.
As
this link demonstrates, scripturally, there is only one way to become a legitimate ambassador of Christ: by appointment from a superior. This can be done in two ways: being commissioned by a legitimate ambassador (apostolic succession), or being called directly by God. Ss. Timothy and Titus were appointed to their positions of authority by succession, Moses and St. Paul were appointed to their positions directly by God, with no human mediation.
Scripture also does not speak well of those who illegitimately take this position upon themselves. In the book of Acts, illegitimate leaders attempted to confuse the Christians by claiming that circumcision was necessary for salvation. The Council of Jerusalem commented upon this, saying: “…we have heard that some persons from us have troubled you with words, unsettling your minds, although we gave them no instructions…” (Acts 15:24). Note well what is presumed here: that it was wrong of these men to act in such a way without first having received their commission, their “instructions,” from those in legitimate authority.