New King James Version (NKJV)
13 And He went up on the mountain and called to Him those He Himself wanted. And they came to Him. 14 Then He appointed twelve,[a] that they might be with Him and that He might send them out to preach, 15 and to have power to heal sicknesses and[b] to cast out demons:
Jesus called his disciples to be with Him. We can be with Him in prayer and fasting and gathering together with other believers. We can join with them on church Sunday celebrations, Bible Studies, Life Groups, and Special events that are to lift up Jesus in worship and praise. Spending time with Jesus gives us power to heal and deliver all the lost souls we will encounter as we are sent out to preach. If you have been called to be a disciple of Jesus spend time with Him in prayer, fasting, and attending church. Be that disciple that will make the difference to a lost world.
Spend some time with Jesus.