Analysis:
This quatrain by Saadi Shirazi paints a poignant picture of unrequited love and the emotional turmoil it causes. Let's break down the deeper meanings:

Unrequited Love: The speaker's tears suggest a deep emotional pain, likely caused by unrequited love.
Misunderstanding: The beloved misunderstands the reason for the speaker's tears, thinking they are seeking pity. This highlights a common theme in love poetry: the difficulty of expressing one's true feelings.
Cultural Barrier: The comparison of the beloved to a "Turk" and the threat of being struck with a polo mallet suggests a cultural or social barrier that prevents the speaker from expressing their love. This could imply a difference in social status, religion, or cultural background.
Hopelessness: The final line conveys a sense of hopelessness. The speaker believes that revealing their feelings would only lead to rejection or even harm.

Themes:

Unrequited love: The central theme is the pain of unrequited love.
Misunderstanding: There is a clear misunderstanding between the lover and the beloved.
Cultural barriers: The speaker faces a cultural or social barrier in expressing their love.
Hopelessness: The speaker feels hopeless about their situation.

Deeper Meaning:

This quatrain captures the universal experience of feeling misunderstood and alone in love. It highlights the emotional toll that unrequited love can take and the barriers that can prevent people from expressing their feelings.

The image of the tears flowing into the water symbolizes the futility of the speaker's attempts to communicate their emotions. The threat of the polo mallet serves as a metaphor for the harsh realities of life and the dangers of revealing one's vulnerability.

This quatrain is a poignant expression of the human condition. It reminds us of the pain of unrequited love and the challenges of navigating complex relationships.