The concept of Ratzo and Shuv:^[1]

The sages state that both the heavens and earth were created for the sake of Torah and for the sake of the Jewish people. Being that this is the case, one must say that there is an aspect of heaven and earth that is found in the Torah as well as in service of G-d through which one is able to establish the physical heaven and earth. The matter is as follows: There exist two different modes of service of G-d, one called Ratzo and the second called Shuv. The service called Ratzo refers to the passion and desire of the heart to cleave to G-d. It comes from the word Ratz, which means to run, as one who is overcome with passion runs towards the subject of his passion to be nullified to it. In general, all the souls of Israel have a subconscious deep passionate desire to cleave to G-d. The divine service of Shuv refers to drawing down G-dliness below, in which we return the G-dliness back onto the earth. So, while in the mode of Ratzo we run towards G-d, in the mode of Shuv, we draw Him down to us. The Divine service of Ratzo is the service that corresponds to the earth while the divine service of Shuv is the divine service that corresponds to the heavens. In today’s times, prior to the redemption, the service of Shuv in which we draw down G-dliness is dependent on preceding it with Ratzo. However, in the future this order will change.

[1] Torah Or p. 1c-d