Ten gratitude persons that we should respect to:
1. sammasambuddha:fully enlightenment buddha
2. pacceka Buddha: individual enlightened Buddha
3. arahant
4, aggasavaka:great chief disciples
5. Mata: mother
6. pitu:father
7.guru:respected person
8. sattha: teacher
9. dhammadesaka: dhamma preacher
10. dayaka: supporter of 4 requisites.

In the past lives, we might make mistakes towards them.
By paying respect to these 10 types of person, we can clear bad kammas.
We can also have more confidence in the mind, and easy to practice meditation.