The Tetractys is:
a pentastich, a complete poem in a 5 lines.
syllabic, with a progressive syllable count 1-2-3-4-10 per line.
sometimes written as a Double Tetractys (2 quintains) , when doubled the syllabic pattern is reversed,1-2-3-4-10-10-4-3-2-1.
sometimes it is stanzaic, written in any number of quintains. When written in multiple stanzas the syllabic pattern is a Mirrored Tetractyssyllables per line 1-2-3-4-10 10-4-3-2-1 1-2-3-4-10 10-4-3-2-1 etc….
Now laid in
His word built home
Clappings alone show him light to his march