Create in me a clean heart, O God; and renew a right (steadfast) spirit within me. Psalm 51:10 When the word sin appears in the singular, it usually denotes the sin nature of humanity. This sin nature is something everyone possesses, it influences us to sin and is the source of lust. That is why Jesus instructed His disciples that man should always pray. Prayer keeps us connect with God, allowing the Spirit of God to control us rather than sin.