וָאֶשְׁמַ֥ע קוֹל־אָדָ֖ם בֵּ֣ין אוּלָ֑י וַיִּקְרָא֙ וַיֹּאמַ֔ר גַּבְרִיאֵ֕ל הָבֵ֥ן לְהַלָּ֖ז אֶת־הַמַּרְאֶֽה׃
And I heard the voice of a man between the banks of Ulai, who called, and said: ‘Gabriel, make this man to understand the vision.’
Read kabbalistic (mystical) interpretation of Daniel 8:16: and classical mystical sources.