What is the main difference in the definition of the holy spirit in Islam and Christianity?

In Christianity, the Holy Spirit is the third person of the Trinity, which includes God the Father, God the Son (Jesus Christ), and the Holy Spirit. The Holy Spirit is believed to be God's presence in the world today that works in believers to guide, empower and equip them.

In Islam, the Holy Spirit (Ruh al-Qudus) is generally believed to be the angel Gabriel (Jibril) who was responsible for revealing the Quran to Prophet Muhammad. It is not considered a part of God, nor is it seen as divine, but rather a high-ranking angel.

So, the main difference lies in the divinity of the Holy Spirit. In Christianity, the Holy Spirit is seen as divine and part of the Godhead, while in Islam, the Holy Spirit is seen as the angel Gabriel and not divine.