While we must be culturally sensitive in foreign countries, we need not do what most missionaries have done in the past—spend years learning the culture and the language of the nation before they shared the gospel.
The biblical gospel message is applicable to all people everywhere—whether they are in the U.S. or overseas, in a high-rise or a lowly hut, rich or poor, happy or hurting, regardless of their beliefs or their lifestyles. We do not need to tailor specific outreaches to each individual group, because the disease of sin and the cure of the Savior apply to all humanity. God has given light to every man, and the universal moral Law is written on the heart of all people in all cultures.
In every nation people have a God-given conscience and a will to live. To be effective (with God’s help), all we need is a good translator and the knowledge of how to tap into the will to live and the human conscience using the Law.
1 Kings 8:43 …hear in heaven Your dwelling place, and do according to all for which the foreigner calls to You, that all peoples of the earth may know Your name and fear You, as do Your people Israel, and that they may know that this temple which I have built is called by Your name.
Ray Comfort's Daily Evidence 
Additionally there are in most nations and languages and cultures, men of God who can preach the gospel to their own people effectively. Maybe investing in further education and support for them is what the Lord would have us do while we focus on our own backyard which is littered with all sorts of destruction from sinful living while ‘civilized’.
I am always blessed and inspired by your posts, God bless you and the work you do for him.
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