Only Jesus can satisfy your soul. Until you have a relationship with Him---until you accept Him as your personal Savior, you won't know perfect peace and contentment.
Isaiah 26:3 Thou wilt keep him in perfect peace, whose mind is stayed on thee: because he trusteth in thee.
A believer with sin in his/her life won’t have contentment until the sin is confessed and forsaken---until they allow God to take first place in their heart and lives.
Those who walk with the Lord in purity have a reason for praise. They enjoy the best this world can offer, and they have hope in the next world as well.