The words, "kingdom of God" appear 32 times in Luke and 15 times in Mark. The word, "salvation" only appears 5 times in Luke and 1 time in Mark. To be fair, I will also include the word, "saved" which appears 7 times in Luke and 5 times in Mark.

To go even further...In the entire New Testament, "kingdom of God" is mentioned 69 times, "saved" is mentioned 57 times and "salvation" is the least mentioned appearing 43 times.

Do you think that churches are and should be preaching the "gospel" of Salvation? And what is the significance in preaching the kingdom of God as Jesus did?

Mark 1:14, "Now after that John was put in prison, Jesus came into Galilee, preaching the gospel of the kingdom of God,"

Luke 4:43, "And he said unto them, I must preach the kingdom of God to other cities also: for therefore am I sent."

Luke 9:2, (to the 12 disciples) "And he sent them to preach the kingdom of God, and to heal the sick."

Luke 9:60, "Jesus said unto him, Let the dead bury their dead: but go thou and preach the kingdom of God."