A hasty analysis would configure David’s sin as adultery and consequent murder of Uriah.
However, we have seen how the tale suggests a change upstream in the king’s attitude, which would represent the source from which flow forth the sins that with a cascade effect culminate in murder.
The type of sin is that of “omission” rather than of “commission”. In other words, any sin of
"commission” implies a previous “omission”, at the deep level of that freedom that one is not
always aware of.
By means of its narration, the text indicates the aim of the sin which is the death of a fellow
man. That is where the seriousness of the sin resides: it leads to death via the murder of the victim
and via the spiritual death of the murderer. It generates the rupture of the communion, it implies the loss of the sense of existence.