What are the three oldest professions

Here's my list:

1. Soldier
2. Priest
3. Artist

I'd say that the profession of a prostitute (female or male, it does
not matter) is the second-oldest. And no, that's not supposed to be a
joke.

Scriptor

Scriptor is right. Prostitute is #1 and politician is close behind.
Come to think of it, there is no difference between the two.

Hunter, gatherer, Shaman.

Mother, Father, Nagging Child.

"The oldest profession" is a euphemism for prostitution

IMO the second oldest profession is footpaddery (mugging)

It's almost impossible to prove exactly which are the three oldest
professions, but you can logically deduct them.

Given that the first human beings were nomads and that they haven't
natural weapons you can surely state that the gatherer was the first
profession of mankind, besides you can affirm that the weapon maker is
the second since the hunter, the third, cannot exist without weapons.

Instead if you mean which are the three oldest professions that are
the unique occupation of a human being, it's more complicated, since
at the beginning of mankind there weren't work division.
In this case you can think that the firsts are both the householder
and the hunter, while the third cannot be said, it can be the
historian (who paint graffiti), the shaman...

"So the LORD God banished him from the Garden of Eden to work the
ground from which he had been taken."
--Genesis 3:23   Adam = Farmer
"Later she gave birth to his brother Abel. Now Abel kept flocks, and
Cain worked the soil.
--Genesis 4:2    Abel = Shephard  (Cain = another farmer, but farmer
is already in my list)
"Cain lay with his wife, and she became pregnant and gave birth to
Enoch. Cain was then building a city, and he named it after his son
Enoch."
--Genesis 4:17   Cain = City builder 

1. Farmer
2. Shephard
3. Builder

And to progress a bit further...
"Adah gave birth to Jabal; he was the father of those who live in
tents and raise livestock.  His brother's name was Jubal; he was the
father of all who play the harp and flute.  Zillah also had a son,
Tubal-Cain, who forged all kinds of tools out of bronze and iron.
Tubal-Cain's sister was Naamah."
--Genesis 4:20-22

4. Livestock raiser
5. Musician
6. Tool maker

Looking even farther back that the last comment, here is the most obvious list:

Gardener ? one who tills, farms and tends gardens
Zoologist ? one who studies and observes animals
Orchard Keeper ? one who tends orchards

In Genesis 2:15-20 God told Adam to cultivate the garden, keep the
garden, name the animals, and eat of the garden's fruit (except from
the tree of the knowledge of good and evil). Initially God gave Adam
three jobs outlined here:

Gen 2:15  And the LORD God took the man, and put him into the garden
of Eden to dress it and to keep it.
Gen 2:16  And the LORD God commanded the man, saying, Of every tree of
the garden thou mayest freely eat:
Gen 2:17  But of the tree of the knowledge of good and evil, thou
shalt not eat of it: for in the day that thou eatest thereof thou
shalt surely die.
Gen 2:18  And the LORD God said, It is not good that the man should be
alone; I will make him an help meet for him.
Gen 2:19  And out of the ground the LORD God formed every beast of the
field, and every fowl of the air; and brought them unto Adam to see
what he would call them: and whatsoever Adam called every living
creature, that was the name thereof.
Gen 2:20  And Adam gave names to all cattle, and to the fowl of the
air, and to every beast of the field; but for Adam there was not found
an help meet for him.

Let me know if this qualifies as an answer.

Tutuzdad-ga

First, gatherer: the man with no tool picking up the most readily
available food in the beginning, and later learning about how to pick
up more difficult-to-get foods.
Second: guard. Immediatly after collecting, people had to protect the
product of their work.
Third: artisan. Collecting led people to the need of turning strong
branches or stones into tools for the job and containers where to keep
the food.
Fourth: shaman / chief: those roles, often merged in one, where needed
to "bring order to chaos" ;-) -- namely, to avoid the in-tribe
fighting for the resources.
Fifhth: hunter/fisher. Eventually, our ancestors understood that with
the appropriate tools they could become able to "collect" fast moving
and tasty things.
Sixth: cook.
Seventh, storyteller: there's always a lie or two to tell about hunting or fishing.
Seventh: artist. Somehow, the fast living thing had to stay still
somewhere to make it easier the hunting.
Eighth: warrior. Now that we have the weapons and know how to use
them, why not going to pick up the stuff of some weaker gatherers, and
the gatherers themselves?
Etc, etc. Actually, prostitution is supposed to be quite a late
development in civilization. It requires some development of the
individual as opposed to the tribe, and the appearence of trade and
money. Primitive exchanges of human sexual services for goods is more
related to marriage -- involving agreements and rituals -- than to
prostitution, whis is actually posterior to the succesive types of
marriage that existed in social evolution.

Guillermo