לעולם ועד

From לְעוֹלָם (l'olám, “forever”) + וָ־ (va-, “and”) + adverbialized form related to עַד (ad, “until”).

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לְעוֹלָם וָעֶד • (l'olám va'éd)

1. for ever and ever
   • Tanach, Exodus 15:18, with translation of the Jewish Publication Society:

     יְהוָה יִמְלֹךְ לְעֹלָם וָעֶד׃

     YHVH yimlókh l'olám va'éd.
     YHWH yimlōḵ ləʿōlām wāʿeḏ.

     The LORD shall reign for ever and ever.