וַיַּנְחֵ֣ם לָ֭בֶטַח וְלֹ֣א פָחָ֑דוּ וְאֶת־א֝וֹיְבֵיהֶ֗ם כִּסָּ֥ה הַיָּֽם׃
And He led them safely, and they feared not; But the sea overwhelmed their enemies.
Read Kabbalistic (mystical) interpretations of Psalms 78:53: Zohar and classical Jewish mystical sources, free online.