WHAT
Let the word of Christ dwell in you richly;
in all wisdom teaching and admonishing one
another with psalms, hymns, and spiritual songs,
singing with grace in your heart to the Lord.
Colossians 3:16

WHY
I have hidden your word in my heart,
   that I might not sin against you.
Psalm 119:11

How
This book of the law shall not depart from your mouth, but you shall meditate on it day and night, that you may observe to do according to all that is written in it; for then you shall make your way prosperous, and then you shall have good success.
Joshua 1:8

When
Do this, knowing the time, that it is already time for you to awaken out of sleep, for salvation is now nearer to us than when we first believed.
Romans 13:11