Answer: Yoda
Luke was told to head to the Dagobah system to look for someone named Yoda, since he would be trained by him to become a Jedi. When he first got to Dagobah, he noticed a creature watching him so he pointed a weapon at the creature. This was when Yoda told him to put away his weapon since he did not mean to hurt him. Yoda then asked Luke why he was there, so he said he was there to locate Yoda. Shortly after this, Yoda introduced himself to Luke.