Analysis:
This quatrain by Saadi Shirazi explores the complexities of human nature and the struggle between spiritual aspirations and earthly desires. Let's break down its meaning:

The Vow of Renunciation: The poet initially vows to renounce worldly desires, particularly love, and embrace a more spiritual path.
The Conflict with Nature: However, the poet soon realizes that this renunciation goes against their natural inclinations. Their heart still yearns for love.
The Return to Love: Recognizing the futility of denying their true nature, the poet decides to embrace love once more. They vow to never repent of this decision.

Themes:

The conflict between spiritual and earthly desires: The poet grapples with the tension between their spiritual aspirations and their natural inclinations.
The power of love: Despite their initial attempts to suppress it, love proves to be a powerful force in the poet's life.
The acceptance of human nature: The poet ultimately accepts their own nature and the inevitability of human desires.

Deeper Meaning:

This quatrain suggests that while spiritual pursuits can be valuable, they should not come at the expense of one's true nature. The poet's journey reveals the importance of balance and harmony in life. The final line, "I repented so that I would not repent again," is a powerful statement of self-acceptance and commitment to one's true self.

This quatrain is a celebration of love and human nature. It suggests that while spiritual pursuits can be meaningful, they should not deny the fundamental human experiences of love and desire.