Their full doctrinal significance emerged in 16th century Lurianic Kabbalah with reference to the cosmic processes of Tohu and Tikun, "Chaos and Rectification".
Man, whose soul reflects the harmonised order of partzufim, rectifies the mundane world by redeeming the exiled sparks of holiness through Torah study and performance of mitzvot.
The realm of Tohu is characterised by abundant light (Ohr) and weak vessels, as the ten sefirot act independently as absolute forces, causing it to collapse.
For example, Arich Anpin, the Partzuf of Keter, means the "Long/Extended Face" as it acts as the foundational Divine Will within Creation, extending down through subsequent partzufim, sefirot and Worlds, though in successively more concealed mode.
The task of man becomes the rectification of the fallen sparks of Tohu, the concealed sublime origins of lower Creation, latently active in their exiled state.
The messianic goal is the union of the original great illumination of Tohu within mature vessels of Tikun, revealing the ultimate divine essence of both.
As Rabbi Shimon bar Yochai recounts in the Zohar: Whatever I said of the Atika Kadisha, Holy Ancient-One, and whatever I said of the Zeir Anpin, is all One; everything is absolutely One.
The terminology and system of partzufim describes detailed and specific aspects of Divinity, their nature and function discussed in Kabbalah.