זוהר שמות — דף רב ע”ב

Parasha Vayakhel — folio 202b. The prayer lingers and ascends through each firmament until reaching the fifth, where an appointed one named Gadriel, master of battles on the left side, orders all conflicts. The Zohar describes how prayer overcomes the forces of the Other Side and rises upward. The names of the appointed ones over each firmament are explained: each is responsible for a particular function in the order of creation. The holiness of prayer is bound to the holiness of the firmaments.