Suus eius latino dating, textkit Greek and Latin Forums
In propria venit, et sui eum non receperunt. There are some exceptions and further complexities that you needn't let bother you for now. That's the quick and easy rundown of the difference between reflexive and non-reflexive pronouns. Sacculus Iulii non parvus est.
The semantic distinction between the two, which you don't seem aware of, is that suus is reflexive whereas eius isn't. This is most commonly true when suus actually agrees with the subject of the clause, in which case it would obviously be nonsensical for the reflexive to refer to the subject being modified. However there are cases when suus doesn't refer to any subject at all, but rather to the principle topic of a clause, daughters and dating quotes or even just of an individual phrase. But suus can just as often refer to a dative antecedent.
This is known as an indirect reflexive, and since se and suus are used for both direct and indirect reflexives, there's a degree of ambiguity introduced by such constructions. If it were written Davus sacculum eius in mensa ponit, on the other hand, it would mean that Davus is setting some other person's mentioned earlier sack upon the table. In sacculo eius est pecunia.
Suus - The Latin Dictionary
Unfortunately the reality, as with most grammatical rules, isn't always quite so simple. That's the general rule of thumb which should serve you well in most cases, at least while you're still at the beginner's stage. Here the nominative sui refers to the accusative eum as its antecedent. The exceptions don't end there, either. Non enim tam praeclarum est scire Latine quam turpe nescire.
Iulius et Aemilia filium suum? Reflexive pronouns are used when they represent the same person or thing that is the subject of the sentence.