Wealth in Islam may be a blessing if it is used for purposes that are pleasing to Allah, and to help one obey Allah. It may be a calamity if it is used for evil purposes, or if it makes one proud and arrogant, or it distracts him from obeying and remembering Allah.

Sadaqah jariyah (ongoing charity) is a charity whose reward continues after a person dies. As for the charity of which the reward does not continue, that is not Sadaqah jariyah. For more, see the detailed answer.