What is the true basis of the brotherhood of man?

Answer

"Have we not all one Father? hath not one God created us? why do we deal treacherously every man
against his brother, by profaning the covenant of our fathers' Mal. 2: 10.

Upon what basis has Christ taught us to ask forgiveness?
What is the ground of justification on God's part?
How does grace, as the ground of justification, exclude righteousness by works?
In what promise was a Saviour from sin first revealed?
Before His birth, what did the angel say to Joseph concerning the naming of the child?
What was first seen on the opening of the sixth seal ?
How often should we pray?

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