\documentclass[a4paper,12pt]{article}
\usepackage{color}
\usepackage{fancyvrb}

\usepackage{xepersian}
\settextfont[Scale=1]{XB Zar}

\begin{document}

\begin{LTR}
\begin{Verbatim}[frame=single,numbers=left,framerule=1mm,rulecolor=\color{red},fillcolor=\color{yellow},framesep=3mm,showspaces=true,commandchars=+()]
\defromanfont\fontname[Scale=+rl(مقیاس)]{+rl(نام قلم)}
\end{Verbatim}
\end{LTR}


\end{document}