Venus begins 25 days in Pisces just before 1 am EST on Saturday morning. Venus will thus be entering the sign where it is exalted. For a planet, exaltation is like being an honored guest in a royal castle, entitled to privilege. That means Venus will be in a friendly place with no agenda beyond its receptive archetype and the sign it occupies. You can therefore expect the development of Venus in Pisces to express itself in a particular, even peculiar way in your life. For many of us it will be like going back to school — the school of fish.
A planet exalted is a potent thing. It is second only to being a ruler among the hierarchy of essential dignities that enhance or diminish the influence of a given planet in a given sign, and much older. Long ago an astrologer named Ptolemy (not the same fellow as the politician/general of ancient Rome, by the way) codified the traditional rulerships we use today. The origin and reasoning of exaltations, on the other hand, is lost to history.
The case of Venus in Pisces, however, makes a lot of sense even if we do not know the original idea behind it. The association between Venus and Pisces invokes the ocean and its inhabitants, but begins in the sky. Long ago, people looked at the stars and projected images upon their distribution. Among those images, called constellations, was Pisces. The tableau is two fish linked in unity. The myth behind the picture is that of Venus and her son, Cupid, transforming themselves into fish to escape the monster, Typhon. The symbolism continues in the sequential order of the modern, tropical zodiac.