This information is critical when it comes to defending the faith, specifically against Muslims who mock the trinity. I hear "so God had to kill God to save us? That doesn't make any sense." Islam started when God asked Abraham to sacrifice his only son Isaac..they believe it was Ishmael and even celebrate the feast of Ishmael. Ishmael was older but was born from Hagar, Abraham's bondservant. When God identifies Isaac as the "only son who you love", it's because Abraham had Isaac with his wife Sarah when he was 100 years old and she was 90. Anyway, Wes does a really nice job pointing out how Yahweh is used for all 3 members of the trinity in scripture. This isn't the best example, but H2O is ice, liquid, or steam, but it's all the same substance. God the Father is spirit and invisible as steam is. Jesus would be the ice or solid who is "God with Us" and the Holy Spirit is the living water Jesus talks about.
Here's the link:
Steve M