... and the mighty-ones... (ibid.) – these are two Tannaim. Eiytanim (mighty-ones) through a switching of the letters are Tannaim (Mishnaic) sages,... the foundations of the earth... – these are: ‘Righteous-One’∞tzadiq (Yesod) and ‘righteousness’∞tzedeq (Malkhut).
Another word: Hear, O mountains... – these are the 3 points which are segol ֶ,... and the mighty-ones... are the two points which are tzeirei ֵ.
And furthermore: Hear, O mountains... Who are the mountains? They are the second set of three points which are qubutz shureq ֻ.... and the mighty-ones... are the second set of two points which are shva ְ.