S - Scripture
Matthew 6 v. 18 That your fasting may not be seen by men but by your Father who is in secret; and your Father who is in secret will reward you.
O - Observation
The very last portion of this verse, "And your Father who see's in secret will reward you", must be very important. Jesus said this 3 times, Matthew 6 v.4, in relation to giving; Matthew 6 v. 6 in relation to praying and then this verse in relation to fasting. All three are spiritual discipline. All related to the heart or motivation of the person doing this. The other cool thing is God never lies and he is all knowing or seeing - so doing these things in private for the Lord will be a blessing.
A - Application
Am I practicing these disciplines in private?
P - Prayer
Jesus, Give me the heart work to do these disciplines. Love Will.