1. The meaning of this sentence is: Be polite and respectful when talking to others, which will make people feel warmer than cloth. Speaking harshly and hurtfully to others will cause great harm to the other person's psychology, which is more serious than stabbing someone with a spear or halberd.
2. From: Xunzi's "Xunzi's Honor and Disgrace", original text: Therefore, good words to others are warmer than cloth; words to hurt others are deeper than spears and halberds.
3. Words can bring pleasure or pain to people. These sentences use the metaphor that good words are warmer than cloth and evil words are deeper than spears and halberds. The image accurately illustrates this feeling and consciousness.