It should always be kept in mind that the Church is a divine family and that its loyalties sometimes cut sharply across the ties that bind earthly families together.
The cross is a sword and often separates friends and divides households. The idea that Christ always brings peace and patches up differences is found nowhere in His own teachings. Quite the contrary is true. For a man to cast in his lot with Christ often means that he will be opposed by his blood relatives and will find his true family ties only in the community of regenerated souls.
Surely it is a most desirable thing to be reared in a Christian home. When a young man or woman is thus happily situated, conversion to Christ brings no rift to the family circle but rather seals and cements the earthly ties. We see sometimes whole families from the aged grandparents to the youngest child all joyously serving the Lord, and hardly anything under the sun could be more delightful. But it is not often so. More often the presence of a true Christian in the home, if it does not actually divide, does at least bring a serious divergence of interest and puts a real strain upon the solidarity of the household.
A. W Tozer