I read this quote from Homer’s Odyssey. 

“Yet taught by time, my heart has learned to glow,

For other's good, and melt at other's woe.”

It reminded me of the verse from Psalms 126:5-6

“Those who sow in tears

Shall reap in joy.

He who continually goes forth weeping,

Bearing seed for sowing,

Shall doubtless come again with rejoicing,

Bringing his sheaves with him.”

I think, with few exceptions, the “Great Commission” is about investing in people; pouring ourselves out for others as Jesus did.  

If we sow the word of God in tears we will see results.