It is not enough that they had sown good seed, but they must take care lest it be plucked up, and tares sown in the stead of it, by the wicked one, Matthew 13:19. A husbandman's work is never at an end, neither is the labourer's in God's vineyard. See how they do; not so much looking after their bodily welfare, as how their souls fared, whether they continued in the faith, and integrity of life.
Related Commentaries of Acts 15:36
Acts 15:36
36 And some days after Paul said unto Barnabas, Let us go again and visit our brethren in every city where we have preached the word of the Lord, and see how they do.