The name of G-d is not complete during exile:[1]
During times of exile, the name of G-d is not complete, as the first half of G-d’s name Havayah, the Yud Kei, is disconnected from the second half, the Vav Kei. This disconnection is expressed in service of G-d in the following way: It is possible for a person to contemplate the greatness of G-d in great depth, arousing a great nullification towards G-d that surpasses intellect and logic, and nonetheless the heart will remain unmoved and emotionless. It will not affect one’s heart to suddenly be overtaken with emotions of love and fear for G-d with a fiery passion and desire. The cause for this is the exile, which refers to the spiritual exile of the soul within the physical lusts and worldly matters. [This immersion of the soul in lusts for physical pleasures desensitizes the heart and emotions from experiencing feelings of spiritual pleasures and desires, even if one’s logic obligates it. In essence, during exile, our heart and emotions are spiritually numbed from the physical world and its pleasures and hence live in a state of disconnect from our mind and intellect.]
[1] Likkutei Torah 18b