A breakdown of statistics, equipment, and abilities for the THIEF class in Final Fantasy (FF, FF1, FFI, NES, Virtual Console)

The Thief is a job available to the Warriors of Light in the original Final Fantasy. Its upgrade is the Ninja (にんじゃ, Ninja?). The Thief and the Ninja specialize in swiftness and evasion, in exchange for not having the same level of offensive power as Warriors and Monks.

Thieves are agile combatants that often have the ability to Steal items during combat. Most Thieves wield daggers, but some equip short swords or boomerangs. Their armor options are limited to lightweight pieces.

Instead of a monk, go with a Thief (Ninjas can equip just about all the fun stuff) or consider adding another Warrior. The game's treasure list is such that you can fully equip two Warriors. As...

The Thief is an unusual character to work with. Though he has decent attacking potential and a passable HP count, his inability to equip the best weapons and armor makes him a second-class warrior compared to the Warrior or the Monk, particularly later on.

The Ninja is a huge improvement over the Thief. While still possessing a superior running ability, the Ninja can equip most weapons and a good amount of armor, as well as being able to cast low-level black magic.

No Steal, no magic, terrible defense, and not that great strength. The Monk can do more damage overall. So since an ideal party is two physical attackers, one healer and one support character...

If you really want to argue that a Thief should be able to steal, then try this. The Thief starts with the most Luck, the stat that helps you successfully run from battle. So having a Thief...

You can solo the game with a black mage easy. With a thief it takes 200+ hours of grinding before you even kill ultos. Thief is the worst.

If we're talking about OG FF1, WM and BM are pretty underwhelming for most of the game and the thief is effectively dead weight because all of the game's bugs work against him, such as the weapon crit % index bug, the run probability bug, and the weapon enemy weakness bug.