usepackage{...}
theoremsytyle{theorem}
newtheorem{thm}{Theroem}
begin{document}
begin{thm}
The equality will holds if one of the following conditions are satisfied:
begin{description}[font=normalfont,leftmargin=0cm]
item[1.] ...
item[2.] ...
end{description}
end{thm}
end{document}