Mark 3:15 explains that Jesus gave the twelve disciples authority to heal sicknesses and to drive out demons. This was not a skill they earned but a commission from Jesus himself, given as part of appointing them to be with him and to be sent out. The verse is narrated by Mark, the Gospel writer, who records what Jesus did on a mountain when he chose the twelve from among a larger group of followers.
And to have authority to heal sicknesses and to cast out demons…
Mark 3:15 (WEB)
What Mark 3:15 Means
The phrase “to have authority” means the disciples were given legitimate permission to act in Jesus’ name. Authority in this sense is delegated, not self-generated. The disciples did not carry power of their own; they carried his. Mark wants readers to understand that the authority belonged to Jesus and was extended to these men for a purpose.
The two activities named, healing sicknesses and casting out demons, are the works Mark has been showing throughout his Gospel up to this point. The verse links the disciples’ future ministry to the ministry Jesus has already been carrying out. It describes what they were to do, not a guarantee that every sick person they met would be healed or that every demonic situation would end on their timetable.
Read carefully, the verse does not promise a permanent or unlimited power available on demand. It describes a commissioning. The rest of the Gospel shows the disciples sometimes succeeding and sometimes failing, so the verse is best read as a description of the mission Jesus entrusted to them rather than a formula for guaranteed results.
The Context of Mark 3:15
Mark’s Gospel is the earliest of the four, and it is written in brisk, action-driven narrative. It was probably composed for a largely Gentile audience, possibly in Rome, and it presents Jesus as the powerful Son of God who acts with urgency. Traditionally the author is identified as John Mark, a companion of Peter and Paul, though the text itself does not name him.
Just before verse 15, Jesus has withdrawn to the mountain and called those he wanted, and in verses 16 to 19 Mark lists the twelve by name. The commissioning in verse 15 sits between Jesus’ choosing and the naming, which shows that the authority was tied to the relationship: they were chosen “that they might be with him” before they were sent out. Reading the verse in this setting makes clear that the mission flows from companionship with Jesus, not from independent ambition.
Key Phrases in Mark 3:15
Matthew 10:1
He called to himself his twelve disciples, and gave them authority over unclean spirits, to cast them out, and to heal every disease and every sickness.
(WEB)
Matthew records the same commissioning of the twelve and gives the same two activities, healing and casting out unclean spirits. Reading the two accounts together strengthens the picture of the disciples’ authority as a gift from Jesus for a specific mission.
John 14:12
Most certainly I tell you, he who believes in me, the works that I do, he will do also; and he will do greater works than these, because I am going to my Father.
(WEB)
In this verse Jesus speaks of believers doing works like his, tying the disciples’ ministry to his own work and his departure to the Father. It helps readers see that the mission Mark describes continues beyond the lifetime of the twelve.
A Short Prayer From Mark 3:15
Lord Jesus, you chose your first followers and called them to be with you before you sent them out. Help me to remember that my service begins with time spent in your presence. Where I feel unready or unqualified, remind me that the authority for good in my life comes from you and not from my own strength. Teach me to act in your name with humility, and let my work point others toward your healing and your kingdom. Amen.
