Martin Luther was primarily opposed to two major things.
The first was the sale of indulgences by the Catholic Church. This was a huge revenue stream wherein you could pay off your sins, no matter how large.
Next, Luther also believed that the Bible alone was the source of divine knowledge and that faith only saved, while the Catholic Church believed in a variety of divinely inspired texts and that faith + good works was the key to salvation.
Supporters of the spoils system claimed it made government more efficient because like-minded individuals cooperated. Opponents claimed it made government less efficient because:Many experienced officials left office after each election