Spiritual works of mercy that relate to the spiritual needs of other people are aimed at alleviating mental suffering. Although spiritual works are obligatory on all believers, in some cases a person may not have the qualities necessary to perform four of the seven spiritual works of mercy, namely: teaching the ignorant, advising the doubting, admonishing sinners, and comforting the sad. These tasks may require a high level of authority and knowledge, or a special sense of tact. The remaining three things - forgiveness of offenses, voluntary forgiveness of evil, prayers for neighbors - are considered capable of being performed for all Christians.