William Burkitt on 2 Timothy 1:5

This is another reason why St. Paul so earnestly desired a sight of his dear son Timothy, namely, a remembrance of his faith, as well as of his tears; which faith is described by the qulaity of it, unfeigned; by the effect of it, it dwelt; by the subjects wherein, in Lois, Eunice, and Timothy; by the order in which, first, in the grandmother Lois, then in the mother Eunice, and lastly, in the child Timothy.

Learn hence, That it is a most desirable and blessed thing when there is a succession of believers in a family, and to see faith transmitted down to posterity, when grandmother, mother, and grandchild, all walk in the truth.

Thus here: And whereas Timothy received the advantage of a religious education from those two holy women, Lois and Eunice, we learn, That God often blesses the labours and examples of holy women, to raise up excellent instruments in his church.