Noah only had to fix his body after his mind healed and his dantian returned to its previous peak. That center of power didn't suffer any injury, but it had lost a lot of energy while it dispersed the drawbacks of his ambition.
Noah couldn't bear seeing his level regress. His addiction toward cultivation didn't allow him to stay put until he regained what he had lost while he recovered.
Many powerful creatures had died during the battle against the quasi-rank 7 Snake. The leader had also eaten some of them in the past centuries. The world had gone from being packed with rank 6 beasts to having only a few of them left.
However, Noah didn't lack food. The quasi-rank 7 ice and the maimed corpse of the Snakes' leader would keep him satisfied for a long time. There was also a chance that they would be enough to bring his body to the peak of the upper tier.