Christianity is missionary 

Jesus summoned the crowd with his disciples and said to them,
“Whoever wishes to come after me must deny himself,
take up his cross, and follow me.
For whoever wishes to save his life will lose it,
but whoever loses his life for my sake
and that of the Gospel will save it.
What profit is there for one to gain the whole world
and forfeit his life?
What could one give in exchange for his life?
Whoever is ashamed of me and of my words
in this faithless and sinful generation,
the Son of Man will be ashamed of
when he comes in his Father’s glory with the holy angels.”

He also said to them,
“Amen, I say to you,
there are some standing here who will not taste death
until they see that the Kingdom of God has come in power.”

The requirement for mission and testimony is so innate and in symbiosis with the Gospel message that Christianity can be clearly defined as being either missionary or not. Therefore, whenever Christians, whatever the role they might play in the Church, for whatever reason do not convey the Gospel, they become guilty of wasting the precious blood shed by Christ and by the martyrs for those who do not receive an announcement. Let us pray that the Lord will give us the necessary fortitude through the Eucharist. (Mk 8:34-9:1)