John Calvin Commentary 1 Timothy 5:7

"These things also command, that they may be without reproach." — 1 Timothy 5:7 (ASV)

And command these things. He means that not only does he prescribe to Timothy the course he should follow, but the women also must be carefully taught not to be stained by such vices. It is the pastor's duty not only to oppose the wicked practices or ambition of those who act unreasonably, but also to guard against every danger, as far as he is able, by instruction and constant warnings.

That they may be blameless. It was the natural result of prudence and steadfastness not to admit widows unless they were worthy. Yet it was proper to give a reason why they were not admitted, and it was even necessary to forewarn the Church that unworthy persons should not be put forward or should not offer themselves.

Again, Paul commends this type of instruction for its usefulness. It is as if he were saying that it must by no means be despised, even though it is common, since it aims at the most important part of a good and perfect life. Indeed, there is nothing that should be more diligently learned in God’s school than the pursuit of a holy and upright life.

In short, moral instruction is contrasted with clever speculations that are of no visible benefit, in agreement with the saying:

All Scripture is profitable, that the man of God may become perfect, and so on (2 Timothy 3:16).