Kalach Pitchei Chokhmah and Tanya

Both texts address the kav (קו) and its relationship to the chalal (חלל). Text 1 (Kalach Pitchei Chokhmah) focuses on explaining how the kav extends/spreads within the chalal ("באיזה אופן הוא מתפשט בו") - an inquiry into the mechanics of the kav's expansion. Text 2 (Tanya) emphasizes the kav as a vessel (כלים) containing divine contraction (צִמְצוּם), comparing it to how the sefirot function as boundaries through tzimtzum. Text 2 frames the kav as the mechanism enabling divine contraction to create limitation (גְּבוּל), while Text 1 appears to focus on the phenomenological question of how the kav occupies and spreads through the void. These represent different analytical angles on the same kabbalistic mechanism rather than substantive contradiction.