Adjust spacing between text and horizontal rule

Question

Please consider the following code:

\documentclass{amsart}
\usepackage{tikz}
\begin{document}
\noindent \tikz\draw(0,0)--(\textwidth,0);
Some Text. More Text. More Text. \newline
\noindent \tikz\draw(0,0)--(\textwidth,0);
\end{document}

Below is a relevant part of the output that will explain the question:

Question

How to reduce the space between the text and the second thin line (the lower one), so that the space between them equals the space between the first thin line (the upper one) and the text?

Answer 1

For dividing text with rules, here's a way. This doesn't ensure equal space between the rules, but the application you have in mind doesn't seem to need it.

\documentclass{article}

\newcommand{\divider}{\vskip2pt\hrule\vskip2pt}
\setlength{\parindent}{0pt}

\begin{document}
Some text

\divider

Some ptext

\divider

Some text

\divider

Some text

\end{document}

If you want that the rule automatically disappears at page breaks, then use

\newcommand{\divider}{%
  \vskip2pt
  \leaders\vrule width \textwidth\vskip0.4pt
  \nointerlineskip
  \vskip2pt
}

Answer 2

Here is a solution.

Note 1: TikZ is not necessary to get the desired result! (Thus, I suggest two solutions...)

Note 2: Look at A line of length \textwidth in TikZ

\documentclass[draft]{amsart}
\usepackage{tikz}

% with TikZ
\newcommand\myhline{%
  \noindent\tikz[baseline=-.35em]\draw(0,0)--(\linewidth-\pgflinewidth,0);\par%
}

% without TikZ
\newcommand\myhlinewotikz{%
  \noindent\rule[.35em]{\linewidth}{.4pt}\par%
}

\begin{document}

\myhline
Some Text. More Text. More Text. \par
\myhline
abc def ghi jkl mno pqr stu vwx yz. \par
\myhline

{
  \LARGE\myhline
  Some Text. More Text. More Text. \par
  \myhline
  abc def ghi jkl mno pqr stu vwx yz. \par
  \myhline
}

\myhlinewotikz
Some Text. More Text. More Text. \par
\myhlinewotikz
abc def ghi jkl mno pqr stu vwx yz. \par
\myhlinewotikz

{
  \LARGE\myhlinewotikz
  Some Text. More Text. More Text. \par
  \myhlinewotikz
  abc def ghi jkl mno pqr stu vwx yz. \par
  \myhlinewotikz
}
\end{document}

Edit: Here is a TikZ solution with minimized vertical spaces (without TikZ, egreg's answer is perfect).

\documentclass{amsart}
\usepackage{tikz}

\newcommand\myhline{%
  \vskip-0.3\baselineskip%
  \noindent%
  \tikz[baseline=-.35em]%
  \draw[blue,dashed](0,0)--(\linewidth-\pgflinewidth,0);
  \vskip-0.3\baselineskip%
}

\begin{document}

\myhline
Some Text. More Text. More Text.
\myhline
abc def ghi jkl mno pqr stu vwx yz.
\myhline

{
  \LARGE\myhline
  Some Text. More Text. More Text.
  \myhline
  abc def ghi jkl mno pqr stu vwx yz.
  \myhline
}
\end{document}

Answer 3

Position of next line is at baseline of next text row. so you need to move starting point of the second line (0,0) for some about above. For this there are more possibilities:

1. Use

   \documentclass{amsart}
   \usepackage{tikz}
   \begin{document}
   \noindent \tikz\draw(0,0)--(\textwidth,0);
   Some Text. More Text. More Text.\newline
   \noindent \tikz[baseline=-1.2ex]\draw(0,0)--(\textwidth,0);
   \end{document}
   

2. Instead of \newline use \\[-1.2ex]

3. Instead \draw(0,0)--(\textwidth,0) use \draw(0,1.2ex)--++(\textwidth,0)

4. Another possibility is to put the text between lines in node and then draw top and bottom border of the box (in this case the text must be shorter than one page ...):

   \documentclass{amsart}
   \usepackage{tikz}
   \begin{document}
   \tikz{
   \node[text width=\textwidth] (text) {
       Some Text. More Text. More Text.};
   \draw (text.north west)--(text.north east)
         (text.south west)--(text.south east);
         }
   \end{document}
   

I hope that this will somehow help you.