Dr. John Whitcomb joins Brannon for another installment of Ask  Dr. John.Question: Was Cain the son of Adam? I heard someone teach that Abel was Adam’s son but Cain was not. Question: Why would there have been “giants on the earth” before the flood, and who were “the sons of God” (Gen. 6:4, NKJV)? Question: Did God send the flood to keep the blood lines pure so Christ could be born? Question: Was Goliath a giant of the same type as these in Genesis 6? Question: In studying God’s covenants, I wonder what Ps. 105:8 means in referring to “a thousand generations” (NKJV)? Question: John 14:1-4 closely follows Jewish wedding customs where the bridegroom prepares a place at his father's house and – when the father feels the time is right – he sends his son to retrieve his bride. The couple then goes to the father's house to enjoy a seven-day wedding feast. For the church, does this correspond with “the marriage supper of the Lamb” (Rev. 19:9, NKJV) and, if so, will it occur immediately after the rapture (during the seven-year tribulation) or at a later time? Question: Please explain the meaning of John 21:25. Question: My pastor teaches that the gift of prophecy (forth-telling, not future telling) is similar to the gift of teaching, but different. He says an easy way to identify the gift of prophecy is when a listener is greatly impacted and convicted by the Holy Spirit completely outside the intent and content of the message given. This just does not sound right. What is the gift of prophecy and how is it different from the gift of teaching or the act of preaching? Question: Are some forms of Christian music too much like the world? The Lord blessed me with musical talent and I would like to join a praise and worship group. Question: Can you please explain presuppositional apologetics?