Given the nature of the work (David is nude and sensually posed), the patron was unlikely to be the Church. Though it was not wholly unusual later to see the church represent its prominent figures in the nude or seminude, this particular piece predates that. Donatello also would not have had the resources to commission this work himself, and David is a biblical figure. It is believed, actually, that the Medici family commissioned the piece for their courtyard. 

The Renaissance literally means "rebirth" and did include a revival of both Greek as well as Roman style, though it is largely agreed that Classical Greece and a renewed interest in its art birthed the Renaissance in Italy. This work is early Renaissance for a number of reasons; one, the piece is not yet the heavily muscled figure reminiscent of Hellenistic Greece and its heroes. Two, the curvature, much like an S-curve, is reminiscent of a lingering Gothic interest. 

This David is depicted the moment after he defeats the giant Goliath. He is standing triumphantly over the giant's severed head, carrying his sword and looking particularly smug over the giant's defeat. He is sensually and salaciously posed in only a hat and boots, and is the only figure of his kind from this time period.

David is fully nude here, wearing only a hat and boots. This is a novel sculptural form for its time, as this is the first time since the end of the Classical era in which a freestanding nude sculpture can be found. The lack of clothing on this young David will set the precedent for more nudity in the Renaissance movement, especially with the works of Michelangelo.

There are a number of controversies surrounding the work, not the least of which is the homoerotic undertones one can see in David's pose, in his face and his open and inviting demeanor. Historians have argued that Donatello was himself gay and this was a representation of that sexual preference. Others say he was commenting on the homosocial Italian society, which condemned but still widely practiced sodomy. Many, though, believe Donatello was simply a pioneer of form. 

In the bible, Goliath is the giant from Gath. He is also, though, the representation of Paganism, especially in the Old Testament. He is withholding the throne from the true king, David, anointed by God. He is meant to represent the end of Pagan culture and rule, suffering at the hands of Christianity and Judaism and the prevalence of those cultures.

While Donatello has carved this figure nude, and donned him with a hat and a sword, it is his pose that is most striking. He is sensual and almost womanlike in his pose, inviting and soft. This is so emphasized because Donatello doesn't know where to draw the line between Gothic s-curved nonsexual figures and the sexual and manly figures of the Classical era.

The answer is Da Vinci. Donatello was dead when this sculpture was made, while Michelangelo, Titian, and Raphael were born either during or after it was being created.

Work is in the public domain, accessed through WikiArt: http://www.wikiart.org/en/andrea-del-verrocchio/david-1475

While all of these were influential, wealthy families around the time of the Renaissance, the famous Medici family commissioned this sculpture along with countless other enduring works of art.

Work is in the public domain, accessed through WikiArt: http://www.wikiart.org/en/andrea-del-verrocchio/david-1475

At first glance, Psyche Revived By Love's Kiss resembles an Ancient Greek sculpture from the Hellenistic period. Given that this sculpture was completed in 1787 - firmly in the 18th century, we must concede that it is neither Ancient Greek nor Ancient Roman. This sculpture is, in fact, an example of Neoclassical sculpture. Neoclassicism as an artistic style was inspired by Ancient Greek and Ancient Roman art and architecture. This style of sculpture is still being produced today.