How to use the memoir package to make a custom title page

Question

There's probably an easy way to do this, but how can I add a memoir title page style to an existing document? I have tried this code, but I still get the basic title page.

\documentclass[12pt,a4paper,twoside]{memoir}
\usepackage[T1]{fontenc}
\usepackage{geometry}
\usepackage{titlesec}  %needs recent version of »titlesec«
\usepackage{xcolor}


\newcommand*{\titleGM}{\begingroup% Gentle Madness
\drop = 0.1\textheight
\vspace*{\baselineskip}
\vfill
\hbox{%
\hspace*{0.2\textwidth}%
\rule{1pt}{\textheight}
\hspace*{0.05\textwidth}%
\parbox[b]{0.75\textwidth}{
\vbox{%
\vspace{\drop}
{\noindent\HUGE\bfseries Some\\[0.5\baselineskip]
Conundrums}\\[2\baselineskip]
{\Large\itshape Puzzles for the Mind}\\[4\baselineskip]
{\Large THE AUTHOR}\par
\vspace{0.5\textheight}
{\noindent The Publisher}\\[\baselineskip]
}% end of vbox
}% end of parbox
}% end of hbox
\vfill
\null
\endgroup}

\title{\Huge\textbf{ORTHODOX RULE OF PRAYER}}
\author{\Large\textbf{Father Thomas Moore, Michael Dykes}}
\date{\Large{\today}}

\begin{document}

\title{\Huge\textbf{ORTHODOX RULE OF PRAYER}}
\author{\Large\textbf{Father Thomas Moore, Michael Dykes}}
\date{\Large{\today}}

Towards evening, we stand before the holy icons (having lit a candle and        maybe some incense), with reverence and fear of God; we gather our thoughts, make the        Sign of the Cross, and say:

\end{document}

Thanks!!!

Answer 1

You only need to create the \drop length and invoke \titleGM in your document (I did two other minor changes, setting the page style to empty an changing the height for the rule to prevent an overfull \vbox):

\documentclass[12pt,a4paper,twoside]{memoir}
\usepackage[T1]{fontenc}
\usepackage{geometry}
\usepackage{titlesec}  %needs recent version of »titlesec«
\usepackage{xcolor}

\newlength\drop
\newcommand*{\titleGM}{%
\thispagestyle{empty}
\begingroup% Gentle Madness
\drop = 0.1\textheight
\vspace*{\baselineskip}
\vfill
\hbox{%
\hspace*{0.2\textwidth}%
\rule{1pt}{\dimexpr\textheight-28pt\relax}%
\hspace*{0.05\textwidth}%
\parbox[b]{0.75\textwidth}{
\vbox{%
\vspace{\drop}
{\noindent\HUGE\bfseries Some\\[0.5\baselineskip]
Conundrums}\\[2\baselineskip]
{\Large\itshape Puzzles for the Mind}\\[.37\baselineskip]
{\Large THE AUTHOR}\par
\vspace{0.5\textheight}
{\noindent The Publisher}\\[\baselineskip]
}% end of vbox
}% end of parbox
}% end of hbox
\vfill
\null
\endgroup}

\title{\Huge\textbf{ORTHODOX RULE OF PRAYER}}
\author{\Large\textbf{Father Thomas Moore, Michael Dykes}}
\date{\Large{\today}}

\begin{document}

\titleGM

Towards evening, we stand before the holy icons (having lit a candle and        maybe some incense), with reverence and fear of God; we gather our thoughts, make the        Sign of the Cross, and say:

\end{document}

To automatically use the information contained in the standard commands \author, \title, some modification is required:

\documentclass[12pt,a4paper,twoside]{memoir}
\usepackage[T1]{fontenc}
\usepackage{geometry}
\usepackage{titlesec}  %needs recent version of »titlesec«
\usepackage{xcolor}

\makeatletter
\newlength\drop
\newcommand*{\titleGM}{%
\thispagestyle{empty}
\begingroup% Gentle Madness
\drop = 0.1\textheight
\vspace*{\baselineskip}
\vfill
\hbox{%
  \hspace*{0.2\textwidth}%
  \rule{1pt}{\dimexpr\textheight-28pt\relax}%
  \hspace*{0.05\textwidth}% 
  \parbox[b]{0.75\textwidth}{%
    \vbox{%
      \vspace{\drop}
      {\Huge\bfseries\raggedright\@title\par}\vskip2.37\baselineskip
      {\Large\bfseries\@author\par}
      \vspace{0.5\textheight}
    }% end of vbox
  }% end of parbox
}% end of hbox
\vfill
\null
\endgroup}
\makeatother

\title{ORTHODOX RULE OF PRAYER}
\author{Father Thomas Moore, Michael Dykes}

\begin{document}

\titleGM

Towards evening, we stand before the holy icons (having lit a candle and        maybe some incense), with reverence and fear of God; we gather our thoughts, make the        Sign of the Cross, and say:

\end{document}