In addition to the "take back the ransom" argument, they said there is no way he could be raised physically because he ascended to heaven. Because "heaven" is a spirit realm, he could not have had a physical body. To support this, they quote 1 Pet 3:18 and 1 Cor 15:45.
Indeed, I have been there with JWs on this.
1 Peter 3:18 (New International Version, ©2010)
18 For Christ also suffered once for sins, the righteous for the unrighteous, to bring you to God. He was put to death in the body but made alive in the Spirit.
Romans 8:11 (New International Version, ©2010)
11 And if the Spirit of him who raised Jesus from the dead is living in you, he who raised Christ from the dead will also give life to your mortal bodies because of his Spirit who lives in you.
The Holy Spirit raised Jesus from the dead, that is what 1 Peter 3:18 also states. It does not state Jesus was only spirit, not physical flesh post.
Paul explains the resurrection body
1 Corinthians 15 (New International Version, ©2010)
The Resurrection Body
35 But someone will ask, “How are the dead raised? With what kind of body will they come?” 36 How foolish! What you sow does not come to life unless it dies. 37 When you sow, you do not plant the body that will be, but just a seed, perhaps of wheat or of something else. 38 But God gives it a body as he has determined, and to each kind of seed he gives its own body. 39 Not all flesh is the same: People have one kind of flesh, animals have another, birds another and fish another. 40 There are also heavenly bodies and there are earthly bodies; but the splendor of the heavenly bodies is one kind, and the splendor of the earthly bodies is another. 41 The sun has one kind of splendor, the moon another and the stars another; and star differs from star in splendor.
42 So will it be with the resurrection of the dead. The body that is sown is perishable, it is raised imperishable; 43 it is sown in dishonor, it is raised in glory; it is sown in weakness, it is raised in power; 44 it is sown a natural body, it is raised a spiritual body.
Clearly the "spiritual body" is of a different kind of flesh to the earthly body, imperishable, honourable, glorified and powerful.
If there is a natural body, there is also a spiritual body. 45 So it is written: “The first man Adam became a living being”; the last Adam, a life-giving spirit. 46 The spiritual did not come first, but the natural, and after that the spiritual. 47 The first man was of the dust of the earth; the second man is of heaven. 48 As was the earthly man, so are those who are of the earth; and as is the heavenly man, so also are those who are of heaven. 49 And just as we have borne the image of the earthly man, so shall we bear the image of the heavenly man.
50 I declare to you, brothers and sisters, that flesh and blood cannot inherit the kingdom of God, nor does the perishable inherit the imperishable. 51 Listen, I tell you a mystery: We will not all sleep, but we will all be changed— 52 in a flash, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, the dead will be raised imperishable, and we will be changed. 53 For the perishable must clothe itself with the imperishable, and the mortal with immortality. 54 When the perishable has been clothed with the imperishable, and the mortal with immortality, then the saying that is written will come true: “Death has been swallowed up in victory.”
55 “Where, O death, is your victory?
Where, O death, is your sting?”
56 The sting of death is sin, and the power of sin is the law. 57 But thanks be to God! He gives us the victory through our Lord Jesus Christ.
58 Therefore, my dear brothers and sisters, stand firm. Let nothing move you. Always give yourselves fully to the work of the Lord, because you know that your labor in the Lord is not in vain.
The JWs I spoke to quoted verse 50 to support their notion that Jesus does not have a physical body. However,
Jesus describes Himself as "flesh and bones" (not just spirit).
Luke 24:39 (English Standard Version)
39 See my hands and my feet, that it is I myself. Touch me, and see. For a spirit does not have flesh and bones as you see that I have."
Indeed, His blood was poured our for many and will not be taken back.
Matthew 26:28 (New International Version, ©2010)
28 This is my blood of the [a] covenant, which is poured out for many for the forgiveness of sins.
- Matthew 26:28 Some manuscripts the new
In His pre-resurrection "natural body" Jesus was flesh and blood John 6:53, John 6:54, John 6:55, John 6:56
When we receive out own resurrection bodies, the resurrection life will be in the Holy Spirit, not blood as the natural body Leviticus 17:11, Leviticus 17:14, Deuteronomy 12:23
Blessings in Christ,