There are two classical definitions of sin by St Augustine:

  1. Sin is anything said, done or desired contrary to God’s eternal law (contra faustum);
  2. Sin is a turning away from God and a turning towards creatures (de libero arbitrio).

For the 1st definition, it states that when sin occurs, laws are broken. God’s eternal law does not necessary mean just positive laws, because what is legal may not be moral and vice versa. It also includes natural moral laws, which are within a person, moving him/her from within rather than from the outside, to do the right thing. Thus when sin occurs, it is viewed as a refusal to love God and others.

For the 2nd definition, there is a 2-fold dimension: the act of turning away from God and turning towards creatures. This would be considered idolatry since it is a deliberate act of turning away from God and turning towards creatures.

The “and” in the 2nd definition should be understood as an “or” because even if one does not turn away from God, nevertheless still cling to creatures or creaturely pleasures, it is a sin of unfaithfulness to God. Most sins occur without actually rejecting God, but merely putting other things above God.

The two definitions of sin by St Augustine are merged in CCC 1849, which defines sin as:

“Sin is an offence against reason, truth and right conscience, it is a failure in genuine love for God and neighbour caused by a perverse attachment to certain goods. It wounds the nature of man and injures human solidarity. It has been defined as, ‘an utterance, a deed or a desire contrary to the eternal law”.

Having defined sin, one might ask ‘Is it possible for one to be sinless’? Well, the answer is NO. It is impossible and unreasonable for one to be free from sin (except Jesus, of course) because all human beings have fallen short of the glory of God. In his/her fallen state, it is not possible for any human being to refrain completely from turning towards creatures or creaturely pleasures.

Understanding our fallen state, Jesus Christ, in his mercy and love, has instituted the Sacrament of Reconciliation to offer us a chance to put right our relationship with God our Father.

How have you put right your relationship with God our Father?

Have you received the Sacrament of Reconciliation in preparation for Christmas? Through this wonderful sacrament of divine love and mercy,

“God called us out of darkness into His wonderful light” (1 Peter 2:9).


Written in thankfulness

Josephine Heng



Fr James Yeo, Christian Morality – A Concise Presentation on The Fundamentals of Catholic Moral Theology, Southbound, 2020.