18:9-15 Where is Sarah thy wife? was asked. Note the answer, In the tent. Just at hand, in her proper place, occupied in her household concerns. There is nothing got by gadding. Those are most likely to receive comfort from God and his promises, who are in their proper place, and in the way of their duty, Lu 2:8. We are slow of heart to believe, and need line upon line to the same purport. The blessings others have from common providence, believers have from the Divine promise, which makes them very sweet, and very sure. The spiritual seed of Abraham owe their life, and joy, and hope, and all, to the promise. Sarah thinks this too good news to be true; she laughed, and therefore cannot as yet find in her heart to believe it. Sarah laughed. We might not have thought there was a difference between Sarah's laughter and Abraham's, ch. 17:17; but He who searches the heart, saw that the one sprung from unbelief, and the other from faith. She denied that she had laughed. One sin commonly brings in another, and it is not likely we shall strictly keep to truth, when we question the Divine truth. But whom the Lord loves he will rebuke, convict, silence, and bring to repentance, and if they sin before him.The promise to Sarah. The men now enter upon the business of their visit. "Where is Sarah thy wife?" The jealousy and seclusion of later times had not yet rendered such an inquiry uncourteous. Sarah is within hearing of the conversation. "I will certainly return unto thee." This is the language of self-determination, and therefore suitable to the sovereign, not to the ambassador. "At the time of life;" literally the living time, seemingly the time of birth, when the child comes to manifest life. "Sarah thy wife shall have a son." Sarah hears this with incredulous surprise, and laughs with mingled doubt and delight. She knows that in the nature of things she is past child-bearing. "Is anything too hard for the Lord?" Sarah laughed within herself, within the tent and behind the speaker; yet to her surprise her internal feelings are known to him. She finds there is One present who rises above the sphere of nature. In her confusion and terror she denies that she laughed. But he who sees what is within, insists that she did laugh, at least in the thought of her heart. There is a beautiful simplicity in the whole scene. Sarah now doubtless received faith and strength to conceive.

Verse 16-33

The conference concerning Sodom. The human manner of the interview is carried out to the end. Abraham convoys his departing guests. The Lord then speaks, apparently debating with himself whether he shall reveal his intentions to Abraham. The reasons for doing so are assigned. First. Abraham shall surely become a nation great and mighty, and therefore has the interest of humanity in this act of retribution on Sodom. All that concerns man concerns him. Second. Blessed in him shall be all the nations of the earth. Hence, he is personally and directly concerned with all the dealings of mercy and judgment among the inhabitants of the earth. Third. "I have known him." The Lord has made himself known to him, has manifested his love to him, has renewed him after his own image; and hence this judgment upon Sodom is to be explained to him, that he may train his household to avoid the sins of this doomed city, "to keep the way of the Lord, to do justice and judgment; and all this to the further intent that the Lord may bring upon Abraham what he hath spoken of him." The awful judgments of the Lord on Sodom, as before on the antediluvian world, are a warning example to all who are spared or hear of them. And those who, notwithstanding these monuments of the divine vengeance, will cease to do justice and judgment, may be certain that they will not continue to enjoy the benefits of the covenant of grace. For all these reasons it is meet that the secret of Lord be with him Psalm 25:11.

10. Sarah heard it in the tent door, which was behind him—The women's apartment is in the back of the tent, divided by a thin partition from the men's. As to those monthly effluviums peculiar to her sex, which are necessary to conception, compare Genesis 31:35.

Now Abraham and Sarah were old, and well stricken in age,.... The one being ninety nine years of age, and the other eighty nine; and which is observed to make it the more surprising that they should have a son at such an age; and what follows still makes it more so:

and it ceased to be with Sarah after the manner of women; her monthly visitors had left her, so that she was unfit for conception, and there could be no hope of it in a natural way; though the philosopher (w) intimates, that there are some, that it is possible, may conceive without them.

(w) Aristot. Hist. Animal. l. 7. c. 2.

Now Abraham and Sarah were old and well stricken in age; and it ceased to be with Sarah after the manner of women.