Recently a friend posted a video of street evangelism in which she was sharing the Gospel with a Muslim. This Muslim young man didn't know much about the Bible and in the course of the convo asked "What is the Holy Spirit?"
My friend used the words "it is..." in her response and went on to try to explain the Trinity as three-leaf clover. Here's the comment I left under her video:
Thanks for the video! Just a few thoughts:
1) Don't refer to the Holy Spirit as "it". He is a person.
2) You used the three leaf clover analogy for the Trinity. I would recommend against using such an analogy.
Here is a small tongue-in-cheek reason not to use that analogy.
It's sarcastic humor. But it illustrates the underlying reason not to use that kind of analogy - the Holy Spirit is fully God, just as the Father and the Son are. They are distinct and yet co-equal, all sharing the essence of divinity equally and fully. The clover analogy does not express the godhead well enough. Of course any analogy fails, but where they fail in a really fundamental way, we should abandon them.
I much prefer to explain the Trinity to a Muslim like this - "The Bible is God's Word. The Qur'an affirms that it is. The Bible teaches that there is one God and only one. It also teaches that the Father is God, the Son is God, and the Holy Spirit is God, and that they are all distinct and yet there is only one God. This is a great mystery. We accept what the Bible teaches b/c it's what God told us." and kind of go from there, showing them in the Bible why we think that is true, if they ask.
A better analogy if you must use one is this: Imagine three balloons of equal size and shape. Each balloon is filled with the same air. Not the same AMOUNT of air. Literally the same air.
How is that possible? It's not, not in this physical universe. That's part of the point. The Trinity doesn't map all that well onto our physical, material experiences.
(HT: SyeTenB for the balloon analogy)