1 Timothy 3:4

one that ruleth well his own house, having his children in subjection with all gravity;

The emphasis in this verse is not upon procreative ability, but upon the ability to rule, a well-disciplined family being the surest evidence of such a trait in one considered for the eldership. Some, discerning this, have gone so far as to declare that:

The requirement is not that an overseer must have children, that a childless man could not be chosen, but that when he has a family, as most men have, any children, should be in subjection.[22]

Even if such a viewpoint is true, which this author doubts, it would be far better to choose able family men with children; and something else should be done, if at all, with the greatest reluctance and with the absolute necessity of doing so if any elders at all were to be appointed. This view is included here because of the usual dependability of its advocate, and not through any agreement with it, but also for the purpose of strengthening the argument for allowing fathers of only one child to be appointed. The overstressing of the "children" requirement has reduced the process of choosing elders in some churches to a mere census of the children!

Regarding the question of whether a man with only one child could be appointed, Zerr has this illuminating comment:

The captain of a sinking ship orders that women with children should enter lifeboats first. This does not mean that women with only one child Would be denied entrance. Sarah remarked (Genesis 21:7), "Who would have said unto Abraham, that Sarah should have given children suck? for I have borne him a son."[23]

Thus, the Scriptural use of the plural "children" to include also the meaning of a single child is fully established from the Old Testament.

Not the number of the children, but their behavior is in view here. Paul would state in the very next verse that a man unable to control his own household should not be entrusted with the government of a church.

With all gravity ... This is not a grace of childhood, but should be applied to the dignity and decorum of the father.

[22] R. C. H. Lenski, op. cit., p. 586.

[23] E. M. Zerr, op. cit. p. 173.