Pain is a given and suffering is optional. Mindfulness of unpleasant feelings, such as pain, can transform pain into fertile soil for wisdom and for freedom from suffering to arise.
Mindfulness of feelings plays a crucial role in our daily life and practice. The arising of feelings is beyond our control but mindfulness of them can make a difference between being in bondage and being free from suffering.
Practicing the 4 protective meditation namely- Reflection on the qualities of the Buddha or Dhamma or Sangha; Reflection on metta, reflection of body parts (visible ones); reflection on death causes and protect us from: Doubt, Attachment, Aversion, Laziness, respectively.
Metta is the quality of the heart/mind that wishes for the welfare, happiness and benefit of all sentient beings. Daily practice of Metta can reduce anger, aversion and lead to joy, happiness and concentration.
All of which is very critical to the path of liberation.