\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{positioning}
\usetikzlibrary{matrix}
\usepackage{xepersian}
\begin{document}
\begin{center}
\begin{tikzpicture}[auto,>=stealth]
\node (N1) {$\llap{$e_2:{}$}N \oplus N_2$};
\node[right=of N1] (L2) {$(N_2,\varphi _{2}\pi)\oplus L$};
\node[right=of L2] (Q1) {$Q$};
\node[above=of N1] (N) {$\llap{$e:{}$}N$};
\node[above=of L2] (L) {$L$};
\node[above=of Q1] (Q) {$Q$};
\draw[->] (N) -- node[swap] {$i$} (N1);
\draw[->] (L) -- node[swap] {$\lambda$} (L2);
\draw[->] (Q) -- node[swap] {$$} (Q1);
\draw[to reversed->] (N) -- node {$\chi$} (L);
\draw[->>] (L) -- node {$\pi$} (Q);
\draw[to reversed->] (N1) -- node {$\chi_2$} (L2);
\draw[->>] (L2) -- node {$\pi_2$} (Q1);
\end{tikzpicture}
\end{center}
\end{document}