# Now the advice of Ahithophel ... was as if a man heard

"Now people trusted the advice of Ahithophel in those days in the same way they would have trusted it if had come" 

# as if a man heard from the mouth of God himself

"as if God had said it with his own mouth" or "as if a man heard it spoken by God himself"

# all of Ahithophel's advice was viewed by both David and Absalom

"both David and Absalom viewed all of Ahithophel's advice"

# was viewed

"was thought of"