Does the Old Testament contain a prediction that Christ/Messiah will rise from the dead? If so where?

I firmly believe in OSAS and that Christ paid for all our sins (past present and future) . So my questions is as Jesus is sitting on the right hand of God interceding for us, what is He interceding for since our sins are already paid for and forgiven?

Re: II Peter 3:10. Will that be a literal fire burning heaven and earth? I believe we will have a new heaven and earth, but I thought the earth would just be repaired. I know that I have read that verse many times, but had it hit me in the face so to speak the other night.

My mother belongs to a church where they give lip service to salvation by Grace, but their deeds and doctrines suggest otherwise. During a discussion she mentioned that most people quote John 3:16 incorrectly, pointing out that “…whosoever believeth on Him should not perish.” is usually quoted “…shall not perish.” The KJV uses ‘should’, while the NIV uses ‘shall.’ She is implying the word ‘should’ leaves the possibility that we might still perish even if we believe on the Lord Jesus. Thus, the need to obey the commandments to prove/show we love the Lord.

Several times you’ve said we’re saved forever and nothing can change that. Doesn’t that mean that Christians are free to do whatever they want without fear of any consequences?

What is the difference between believing and accepting? I’ve always thought I am saved because I believe Jesus died for my sins. But I hear others say they’re saved because they’ve accepted Jesus as their Savior. Is there a difference?

Could you explain the three hundred ninety days and forty days prophecy in Ezekiel 4:6. Does this apply to the regathering of Israel or the re-unification of Jerusalem or both?

Re: 1 Samuel 24:3 “And he came to the sheepcotes by the way, where [was] a cave; and Saul went in to cover his feet: and David and his men remained in the sides of the cave.” What does it mean to “cover his feet” and why would he not have heard David cutting off a piece of his skirt?

I came across scripture below from Acts 24:17 today as I was reading. If Paul was the Apostle to the Gentiles, and Jesus died once and his death paid the price for all of our sins, then why was there a need for Paul to make offerings at the temple? In other words, why was he still arduously keeping the law? Could you please clarify this for me? There is so much confusion with the rise of the Messianic Christian Movements and their penchant for law-keeping and this disturbed me. As a Follower of Jesus, I thought we had no need to keep the law in this manner. But after reading this scripture, I am a little confused.

Please help me understand the end times as they are being played out today. The most difficult thing to find out is, who is the modern day Israel ? Are we being deceived into error? Who and where are the true Jews that we are to bless and love that are God’s true people. Please try to keep it simple for me, thanks.