Gemara: Mishna: There are three things a man must say within his home as Shabbat is about to enter: "Did you take tithes? Did you take part in the eiruv? Light the candles." Gemara: From where do we know this? "You shall know that there is peace in your tent and relate to [the situation in] your home, and you shall not sin" (Iyov 5:24).

Ein Ayah: The final purpose of every positive and negative mitzva in the Torah is the impression of goodness and sanctity it makes on the soul. Therefore, those things that follow the proper set custom in good Jewish homes have full value when the master of the house is fully apprised that they were done properly. The realization on his part brings the influence into his heart. That is why he should ask members of his household.
This is his way of knowing that there is peace in his "tent," with the laws of the Torah being observed within. When he takes an active role in the observance in the home, the whole house is elevated along with him. The good things that go on should be by virtue of his instructions. If things occur on their own, it gives the impression that they are not fundamental to the functioning of the home and that matters could carry on without them. The master of the house must show that the mitzvot are the foundations. This is the matter of "relating to the situation in one’s home" and knowing that there is peace. This is the assurance that "you shall not sin."
The entrance of the holy Shabbat is the time when Jewish sanctity shines brightest and strongest. That is the time to ensure that the operation of the home is being done in the best possible way, which shows that the proper form of a proud Jewish house is in place.

Power of Mitzva Over Discipline
(condensed from Ein Ayah, Shabbat 2:193)

Gemara: Rabba bar Rav Huna said: Even though the Rabbis said, "There are three things that a man has to say …," it must be said in calmly. Rav Ashi said: I did not hear this in Rabba bar Rav Huna’s name, but I fulfilled it based on logic.

Ein Ayah: Every matter that needs decisions contains a "close action" and a "distant action." The close action relates to the specific matter at hand – to act or to refrain from action. The distant action relates to the important results that will occur in the future as a result.
In any apparatus of authority, there are two approaches: pleasantness and aggressiveness. The authority can either act gently or with a strong arm. Regarding the specific matter before us, better results come from speaking and acting gently than from acting aggressively or indirectly. However, there is value in the authority asserting its power, as it strengthens the ability to intimidate rebellious people who in some future case would not be willing to follow decisions. Thus, a seemingly unnecessary display of authority has some added value.
However, regarding mitzvot, we know that their fulfillment, in and of themselves, purifies the mind and heart of the one who performs them. Therefore, in this regard, whether in terms of the close action or the distant one, the gentle approach is sufficient. It not only will cause the mitzva to be done in the present but also intrinsically improves prospects for the future. That is what Rabba meant by the master of the house giving the instructions calmly. It will be effective in the short term, and the mitzva will "drag along" another mitzva.
The above discussion is on the assumption that the critical matter is the long-term prospect of fulfillment. However, Rav Ashi said that without even considering the future, the approach to take in any case is, logically, the gentle approach.