It is based on the "Portrait Chinoix" of a friend (Main, Vague, Pensée bleue), on the number 5, and includes a longer line and a non rhyming middle line (like the middle finger), and one inverted rhyme (me gave/une vague).
There are 5 continents, but only one world, there are 5 elements but only one body (mind/soul, they are one), there are 5 senses but only one lover (un seul amant).
Et il ne saurait en être autrement.
There can be only one lover at a time, only one love. I think that true friend are lovers we do not have sex with, and the ONE friend with whom you are physically intimate with is the ONE and only lover, who has the right to be touched by “the hand” alone (“the hand is alone in touching”)

De nos sens il est le port,
A l’amant seul est le corps.
Ecoute, goûte et sent, parfois
Souhaite de le voir demain :
Au toucher, seule est la main.

Des continents jamais ne tombe,
L’âme seule perçoit tout son monde.
Les cinq terres n’ont qu’une loi :
De faux airs le cœur ne gave ;
L’étoile d’Inde est une vague.

L’amour, ce cinquième élément,
Ne fait qu’un avec l’amant.
Terre, enfer et ciel ont foi :
Le désir d’une pensée peut,
Faire d’une homme une pensée bleue.

Or in English, it translates (but does not rhyme):

To our senses it gives harbour,
To the lover only is the body.
Listen, taste and smell, sometimes even
Whish to see him tomorrow:
Alone is the hand in touching.

It never fell from any continent (Christians associate “sin” with the “sinful fall” of the soul to earth…)
Only the soul finds the world out (“perceives everybody straight away”)
The five lands know only one law:
Do not fill hearts with false hopes;
The Indian star is a wave.

Love, the 5th element, (see the film “the 5th element” by Luc Besson)
With the lover makes only one (“the lover an d love make one”)
Hearth, Hell and Heaven have faith:
The desire of a though can, (“une pensée peut”)
Turn a man into a “pensée bleu”. (“blue pansy”, it sounds romantic in French, it sounds queer in English…).