Christ Ahnsahnghong is God?!?

OK so I've studied the prophecies... and I've still got questions and i cant really bring to the surface i guess... But here i can try!!! My Family has started to question me, especially my Mom. She wants to know who is Ahn sahng hong. So i tried to tell her that hes God but she didn't buy it! Then i was trying to show her in the bible about Jesus and 2nd coming Christ! BUT:

Well the Old Testament testifies about who? Jesus, right!(check Luke24: 13-27). In verse 27 Jesus even tells us beginning with the books of Moses (the Pentetush -gen. ex. lev. numb. det.) and the phropehts (Joshua, Isaiah, Ezikel, Daniel etc. etc.). Meaning the Old Testament testifies about Jesus. but curiously enough NO WHERE in the Old Testament does it mention Jesus name only Jehovah's name can be found. BUT when Jesus came you can find all kinds of references to Jesus ONLY in the New Testament. But then Jesus testified that he will come again in the New Testament (as i mentioned a billion times before).

Then should we see 2nd coming Christ's name in the New Testament? No, because he was to come later on. That way we can recognize him! Same as Jesus Christ. His name was NOT mentioned in the Old Testament but in the New Testament his name was written. Then the same will happen when Christ Comes a 2nd time... his name will not be written in the Old or New Testament..... But we can recognize him by him fulfilling the prophetical points!

So then I really tired to explain this to her but im confused as is many people about the Trinity? what is that... has anyone heard of it?