What determines whether one is a child of Abraham?

Answer

"Know you therefore that they which are of faith, the same are the children of Abraham." Gal. 3: 7.
NOTE - Because of unbelief many of the Israelites fell in the wilderness, and were not permitted
to enter the promised land. Num. 14:27-33; Deut. 1:34-36.

How does the death of Christ bear testimony to this?
Does it matter what one believes, so long as he is sincere?
Why was woe at this same time proclaimed to the world?
In what was shown the first tangible evidence of this \"falling away\" from the truth of God?
What are God's people told to do at this time?
Why is it better to go to the house of mourning than to the house of feasting?
By what does one gain the victory over the world?

Questions & Answers are from the book Bible Readings for the Home Circle