Why Pray if God predestined the future?
One reason is that we are told to do so. Also, God can honor prayer, if he chooses……and even pre-empt nature, i.e. Miracles! We must remember that though He has revealed his nature, there is much mystery left that we will not know. We cannot explain the Trinity, the triune essence of the Godhead, nor can we understand the mystery as to how the Son could be forsaken on the cross. It would seem that the Son is separated from the Father! Mystery! We have been given much in natural and written revelation. We need to focus on what we do understand and leave the rest to YHWH, and the Son, Christ, and the Spirit, the third Holty person. We should give thanks that we are invited before the Sacred Throne and that Jesus modeled prayer for us, the one we labeled The Lords prayer or the Our Father. Actually, it was primarily a pattern or model for which the disciples had asked. The High Priestly, or actual Lords Prayer, in my thinking is in John 17. In the prayers of Jesus, we find that we should pray prayers of intercession. That tells me that we know we can and should. As to how God handles it……its a mystery!