"O my God! I am heartily sorry for having offended Thee, and I detest all my sins, because I dread the loss of heaven and the pains of hell; but most of all because they offend Thee, my God, who art all-good and deserving of all my love. I firmly resolve, with the help of Thy grace, to confess my sins, to do penance, and to amend my life" (Traditional form of the Act of Contrition as found in the Baltimore Catechism no. 3 and the Penny Catechism). [see footnote 1]
When we talk about an "act," we often mean something which we do—an action. Thus, an "act of kindness" means something which we have done for somebody else out of kindness. But now think about this again: an "act" of kindness is often thought of as "small." An act of mercy is certainly something small which we've done, or we might call it rather a "work" of mercy. Thus, instructing the ignorant is a work of spiritual mercy, or feeding the hungry a corporal work of mercy; they take effort and commitment. Raising children is a "work" of love—but merely kissing your child goodnight is by contrast an "act" of love.
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