An important aspect of the miracle is manifested as Jesus lifted the woman by the hand, and the fever left her. The laying on of His hands (see Hebrews 6:2) was something He did often. He even touched lepers, though the Gospels never mention Him laying hands on a demon-possessed person. Through His hands flowed the power of the Holy Spirit, producing immediate restoration to health.
Another feature of this miracle is the way He infused full strength into the woman, enabling her to serve her guests. Her recovery did not include a period of weakness and exhaustion, which usually follows a high fever, but she at once became energetic and full of health. The restoration of her health must have encouraged great gratitude, which manifested itself in service to Jesus and the others there.
This sets a pattern for all who are healed, both physically or spiritually: They should use their new strength to serve God and His people with thankfulness (I Thessalonians 5:18). Peter exhorts, "If anyone ministers [serves], let him do it as with the ability which God supplies, that in all things God may be glorified through Jesus Christ" (I Peter 4:11).
Martin G. Collins
The Miracles of Jesus Christ: Healing Peter's Mother-in-Law