The spring from which they drew
Figuratively: the source of their inspiration. The source of their strength.
(Modern Hebrew, following the poem of Bialik "If You Have the Soul to Know")
Translation
Expression (Hebrew)
הַמַּעְיָן מִמֶּנּוּ שָׁאֲבוּ
Definition (Hebrew)
בְּהַשְׁאָלָה: מְקוֹר הַשְׁרָאָה שֶׁלָּהֶם. מְקוֹר כּוֹחָם.
(הָעִבְרִית הַחֲדָשָׁה בְּעִקְבוֹת שִׁירוֹ שֶׁל בְּיָאלִיק "אִם יֵשׁ אֶת נַפְשְׁךָ לָדַעַת")