2091 The first commandment is also concerned with sins against hope, namely, despair and presumption:
By despair, man ceases to hope for his personal salvation from God, for help in attaining it or for the forgiveness of his sins. Despair is contrary to God's goodness, to his justice - for the Lord is faithful to his promises - and to his mercy.
2092 There are two kinds of presumption. Either man presumes upon his own capacities, (hoping to be able to save himself without help from on high), or he presumes upon God's almighty power or his mercy (hoping to obtain his forgiveness without conversion and glory without merit).
~ Excerpt from Catechism of the Catholic Church ~