Analysis:
This quatrain by Saadi Shirazi offers a profound insight into human relationships, particularly the complexities of friendship and enmity.

The Paradox of Friendship: The quatrain presents a paradoxical situation: if someone chooses the speaker's enemy as a friend, the speaker is powerless. No matter what the enemy does, the speaker will continue to be the "poor" one.
Unconditional Love: Despite the enemy's actions, the speaker expresses unwavering affection, suggesting an unconditional love that is blind to the enemy's faults.
The Power of Love: The speaker's love is so profound that it can withstand any hardship or injustice, making the beloved seem even more desirable.

Themes:

Unconditional Love: The central theme is the power of unconditional love and its ability to endure hardship.
Betrayal and Friendship: The quatrain explores the complexities of friendship and the pain of betrayal.
Inequality and Powerlessness: The speaker's position of powerlessness highlights the inequalities that can exist in relationships.

Deeper Meaning:
This quatrain offers a philosophical reflection on the nature of love and human relationships. It suggests that true love is often blind to the faults of the beloved, and that it can endure even in the face of betrayal. The speaker's unwavering affection, despite the enemy's actions, is a testament to the enduring power of the human heart.

This quatrain is a powerful exploration of the complexities of human relationships, highlighting the enduring nature of love and the resilience of the human spirit.