Commentary for Judges 5:27

Between her feet he sank: He sank in front of her, upon his feet. And he fell immediately to the ground and remained prostrate; and he did not rise again. And that is to say, he was killed very quickly. And she repeated the words for emphasis, and in the way of verse.

Between her feet he sank, he lay: Such is the custom of the language to repeat the words in order to strengthen them. And the content is that he sank a sinking, from which there would be no getting up. And that is what is stated, "where he sank, there he lay - destroyed." And there is a homiletical teaching about it - though it is distant - that between [all the mentions of] sank, lay and fell, there are seven. So they said that that wicked man had sexual intercourse with Yael seven times on that day. But what they wrote above (Judges 4:18) about the word, "semikhah (blanket)," contradicts this teaching.

Where he sank: In the place where he sank, that is where the destroyed and disgraced Sisera fell. For he could not strengthen himself again after the sinking. And this is from the poetics of verse, as he did not truly sink nor fall (as he was already laying down).