אִֽמֲר֣וֹת יְהוָה֮ אֲמָר֪וֹת טְהֹ֫ר֥וֹת כֶּ֣סֶף צָ֭רוּף בַּעֲלִ֣יל לָאָ֑רֶץ מְ֝זֻקָּ֗ק שִׁבְעָתָֽיִם׃
The words of the LORD are pure words, As silver tried in a crucible on the earth, refined seven times.
Read kabbalistic (mystical) interpretation of Psalms 12:7: and classical mystical sources.