Psalm 122:7, "Peace be within your walls, and prosperity within your palaces," is a prayer for the well-being and flourishing of Jerusalem. Let's break down the meaning:

"Peace be within your walls": This refers to the walls of Jerusalem, which were the city's defense and protection. "Peace" here signifies more than just the absence of conflict. It encompasses:
Security: Safety from external threats and internal strife.
Harmony: Unity and good relationships among the people living within the city.
Order: A stable and well-governed society.
Tranquility: A sense of calm and well-being.

"Prosperity within your palaces": "Palaces" represent the centers of power, government, and wealth in Jerusalem. "Prosperity" means:
Abundance: Material wealth and financial stability.
Flourishing: Growth, success, and thriving in all areas.
Justice: Fair and righteous governance within the ruling structures.
Blessing: God's favor and provision upon the leadership and the city.

Overall Meaning:

The verse is a prayer for the comprehensive well-being of Jerusalem. It desires that the city be secure, harmonious, and prosperous, not only in its physical defenses but also in its government and its people's lives. It's a holistic blessing, wishing peace and stability for all of society, from the common people within the walls to the rulers in the palaces.

Symbolic Interpretation:

Beyond its literal meaning, the verse can be interpreted symbolically:

Walls: Represent personal boundaries, inner defenses, and spiritual protection.
Palaces: Symbolize the centers of influence in our lives: our homes, workplaces, and communities.
Peace and Prosperity: Represent inner peace, spiritual well-being, and flourishing in all areas of life.

In this sense, the verse becomes a prayer for peace and prosperity within our own lives, our families, and our communities. It is a desire for wholeness, stability, and blessing in every aspect of our existence.