זוהר שמות — דף כה ע”א

The five expressions of redemption — and I took out, and I delivered, and I redeemed, and I took, and I brought. The greatest of all is the exit from slavery, as they thought they could never leave. 'And I will take you to Me as a people' — this is the greatest gift the Holy One gives to Israel. The four cups of Passover correspond to the first four expressions.