Luke 10

"After these things the Lord appointed seventy others also, and sent them two by two before His face into every city and place where He Himself was about to go." v.1

Read chapter 10
Did you ever realize that Jesus sent out more than just the twelve to heal the sick and preach the Kingdom of God?  There were commissioned specifically by the Lord and this sending is the Greek word apostello.  These 70 had the title of Apostle during this specific time that they went out until the returned.
Does this number seventy remind you of something else in scripture?  Recall from Numbers 11:

 So the Lord said to Moses: “Gather to Me seventy men of the elders of Israel, whom you know to be the elders of the people and officers over them; bring them to the tabernacle of meeting, that they may stand there with you. 17 Then I will come down and talk with you there. I will take of the Spirit that is upon you and will put the same upon them; and they shall bear the burden of the people with you, that you may not bear ityourself alone.

Seventy men were chosen to help Moses lead the people and were given the Spirit to do this.  So we see here in Luke the Jesus gives these seventy men the Spirit to do the Lord's work.  Also the Sanhedrin was made up of seventy elders and headed by the High Priest after Moses and his seventy.
This wasn't to 70 different cities but to 35 different cities as Jesus sent them in pairs.  Each is sent with a companion to do the Lord's work and not go it alone.  It is so important to do life and ministry with others and not alone.  It brings joy, thankfulness, support, accountability, deeper relationship, and so much more.  Yes it can be hard if we're paired with someone completely different than us but let that refine you than destroy you.  

"Two are better than one,

Because they have a good reward for their labor.

10 

For if they fall, one will lift up his companion.

But woe to him who is alone when he falls,

For he has no one to help him up.

11 

Again, if two lie down together, they will keep warm;

But how can one be warm alone?

12 

Though one may be overpowered by another, two can withstand him.

And a threefold cord is not quickly broken." Ecc. 3:9-12

With whom are you doing ministry?