Open Theists aren't Deists.
We don't claim that God is inactive in our lives. We don't claim that God does NOTHING. We believe what the Bible teaches about God, that God is living, personal, relational, good, and loving. We believe what the Bible teaches about God, that He is free and able to change the future.
We believe the Bible when it teaches us that God LOVES us and has emotions.
We believe the Bible when it teaches us that God has control over His own faculties and can know what He chooses to know and can also NOT KNOW what he chooses NOT to know.
We believe the Bible when it teaches us that God doesn't have to be present in every single minute location within the universe in order to be it's God and be in control of it.
We believe the Bible when it teaches us that God is CREATIVE, and can call new things into existence that never existed before.
We believe the Bible when it teaches us that God is RELATIONAL, that He desires a RELATIONSHIP with mankind, and that He HAD a relationship with Himself within the trinity from eternity past.
We believe the Bible when it teaches us that God is love, and that love is far more important than prophecy or knowledge. Thus to God, how much LOVE He has is far more important to Him than the amount of knowledge or power He has.
We believe the Bible when it teaches us that God IS where He wants to be, KNOWS what He wants to know, and DOES what He wants to do.
We believe the Bible when it teaches us that God desires that all men come to know Jesus Christ as Savior.
We don't believe that God is irrational, desiring things to happen that He knows absolutely certain will NOT happen, or worse yet, that He has CHOSEN NOT to happen. (Yes it certainly makes sense to KNOW what is going to happen, to CHOOSE what is going to happen, and then to DESIRE some other outcome). :noway:
These are but a few things that mark the Biblical Open Theist's views on God.
FS- To your OP, we trust God because He is trustworthy. He always has our best interest in mind, and He works in our lives through the Holy Spirit who lives in us.
Thanks for reading, I hope this clears some stuff up.