Morally Good vs Morally Bad

To what extent can we differentiate between morally good and morally bad?

Morally good, the broad sense of this term that embraces a variety of particular virtues such as courage, justice and so on of the same sort. Morally bad, an action may be considered to be wrong because: it is harmful, it is unjust and unfair. Morally good examples can be always telling the truth, not being judgmental, keeping promises, and so on. Morally bad examples are murder, theft, lying, etc. But these are all vague. 

To define a fact as morally good or morally bad is challenging. There's still widespread disagreement on moral matters. How can we apprehend moral facts in this way?  For example, the statement "killing is wrong" is simple, and we can easily understand that killing is bad. But we can't say killing is completely wrong, killing a person for no reason can be defined as morally bad and wrong, but someone can kill a person to stop them from setting fire to a school full of innocent children. Actions have a range of different motives and unseen background facts. To know if something complex is moral, we need to know the cause mainly and their actions, the idea behind the action and the intended effect. Until and unless we know everything that led up to the event, we cannot possibly come to a conclusion. 

Since morality is the system through which we determine right and wrong conduct and it's not like ethics, which means philosophical study of morality. Our emotions and our knowledge help us understand what is right and what is wrong. What one may define as morally right, another may disagree and define it as morally incorrect. Our opinions on situations decide between the two. 

In conclusion, I would like to say that defining a statement or a situation as morally right and morally wrong will be contentious.