1 Timothy 3:4

One that ruleth well his own house
His family, wife, children, and servants; and is not to be understood of his body, and of keeping of that under, and of preserving it chaste and temperate, as appears from what follows:

having his children in subjection with all gravity;
keeping a good decorum in his family; obliging his children to observe his orders, and especially the rules of God's word; and not as Eli, who did not use his authority, or lay his commands upon his sons, nor restrain them from evil, or severely reprove them for their sins, but neglected them, and was too mild and gentle with them; 1Sa 2:23 3:13
but like Abraham, who not only taught, but commanded his children and his household, to keep the way of the Lord; ( Genesis 18:19 ) and so should those act who are in such an office as is here treated of; and should not only rule well in their families, preside over them, go before them, and set an example to them, and keep their children in obedience and subjection; but this should be "with all gravity": not only in the master of the family, but in the children; who as their father is, or should be, should be brought up in, and used to gravity in words and in dress; and in the whole of their deportment and conversation. This may he observed against the Papists, who forbid marriage to the ministers of the Gospel.