#!/bin/bash
text="Title 1 2 3"
filter="-vf drawtext=fontfile=/tmp/freefont1.ttf:text=$text"
ffmpeg -xerror -f lavfi -i testsrc -t 10 "$filter" out.mp4
exit $?

====================
ffmpeg -f lavfi -i testsrc -t 10 '-vf drawtext=fontfile=/tmp/freefont1.ttf:text=Title 1 2 3' out.mp4
ffmpeg version 2.7.2 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.8.3 (GCC) 20140911 (Red Hat 4.8.3-9)
  configuration: --prefix=/tools --extra-cflags=-I/tools/include --extra-ldflags=-L/tools/lib --pkg-config-flags=--static --enable-gpl --enable-nonfree --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libvpx --enable-libx264 --enable-libx265
  libavutil      54. 27.100 / 54. 27.100
  libavcodec     56. 41.100 / 56. 41.100
  libavformat    56. 36.100 / 56. 36.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.100 /  1.  2.100
  libpostproc    53.  3.100 / 53.  3.100
Unrecognized option 'vf drawtext=fontfile=/tmp/freefont1.ttf:text=Title 1 2 3'.
Error splitting the argument list: Option not found