Mary has known Jesus' deep love for her and her family and she responds in loving devotion to Jesus. God uses her to anoint Jesus' body to prepare Him for burial in an extravagant and fragrant way.
Those who trust in Jesus see Him as infinitely precious, and they respond to His love with Holy Spirit-led loving devotion to Him. This loving devotion sees the Word of His Gospel as a fragrant delight both to hear and to speak. His Word and His love move us to turn away from sin and toward acts of extravagant love for each other. These things done to earn God's love would be a terrible stench to God, but as they are done in response to what Christ has done to save us, they are a fragrant aroma to God.