Just throwing it out there, why the extreme of loss of life?.

A few facts we need to deal with:

1/ the event occured post-Pentecost, therefore, they had this right.

For consideration: Why do you, and not them?

2/ excommunication, "the most severe censure" (newadvent.org) was a known disciplinary practice, even in Jewish circles.

3/ Acts 8:20 (Peter is also peaved at Simon Magus for scheming and buying favors, and, he
is known to be an iconoclast and a schemer, however, despite the same context involving
money and with a more sinister motive, he receives the first excommunication.

4/ the Church could ecclesiastically forgive Aninias and Saphira.

5/ Saphira was a housewife of antiquity, not a participant in the financial decision making of the household. The position was more a serviant duty, not like today. Even if she could voice an opinion, it would not carry official weight. (Rawls,Theory of Justice "....consideration would be given to the least advantaged"). If some justification could be given for Aninias's sentence, does his wife deserve a less severe sentence?.

6/ we lie to God when we sin by breaking out baptismal promise or sever our friendship with God.

Marcus