How to initialize a "Text"-property without raising an "OnChange"-event

How can I change the contents of a component (i.e. the "Text"-property in
the "TEdit"-class) without getting a "OnChange"(/"OnClick")-event. The
problem is that if I initialize a TEdit-Field a "OnChange"-event will be
thrown which normally has to respond to an useraction.

For example if the "OnChange"-event shows a messagebox this messagebox
also would be shown when the program is started and the TEdit-field is

An other problem can occur, if you have two components, that change each
other if a "OnChange"-event is received:

procedure Form1.Edit1OnChange(Sender:TObject);
  Edit2.Text := 'EDIT2: ' + Edit1.Text;

procedure Form1.Edit2OnChange(Sender:TObject);
  Edit1.Text := 'EDIT1: ' + Edit2.Text;

this code will lead to an endless loop.