I am in total agreement with everything quoted here. I am not in agreement with the idea that the simple fact that a person studies the OT, or the bible for that matter, means they must have been born again (regenerated). It seems to be saying that any APPEARANCE of interest in biblical things can only come from the new birth. Satan himself is knowledgable of the Bible. Jesus said many would come to him and point to their good deeds done in his name, and he would say "Depart from me, I never knew you."
Forest seems to be saying that if they had that bible head-knowledge, or if they were doing any good deeds, then Jesus actually does know them,..they are His. Even though they reject him, and do not have the belief in Him that is the evidence of the new birth. (see back to 1 John).
I'm not saying depraved man can do anything good in God's sight. I am saying that a depraved, unregenerate, unelect man CAN learn some head-knowledge about the Bible without that in itself being evidence of the new birth.