Rebbe Nachman interprets Judah as faith and Joseph as knowledge. We place this interpretation in the sefirah of knowledge. In short, the idea is that there are two types of questions about Divinity in this world: Questions that have answers and questions without answers. To find answers to the first type, one must exert great effort to study, investigate, and understand—this is the toil of the mind, or Joseph. Not doing so can lead to inner heresy, creating internal conflict between the heart and the mind. But one must acknowledge that there are questions for which, in this world, no answer exists. In such cases, one must strengthen themselves with simple faith—this is the toil of the heart, or Judah. As simple faith becomes more tangible, it transforms into a known reality, it becomes revealed and evident to me. Again, the proper relationship between knowing and faith needs to be struck in life.
In the future, all faith will become included within knowledge, within Joseph, which is why “Judah approached him”—faith aspires and yearns to be integrated into knowledge.