I will even betroth thee unto me in faithfulness,.... Which lies in keeping the marriage contract inviolable; Christ will never suffer his faithfulness to fail, nor break his covenant; as he is faithful to his Father that appointed him, so he is, and will be, to his church and people, and to every believer, to whom he is espoused; and it is he that makes them faithful unto him, and gives them faith to believe in him, receive, embrace, own, and acknowledge him as their husband: and in this sense some understand it, rendering it, "in faith" ; so the Targum and others.
This is the third time the word "betroth" is used, or this promise made; which, according to Jerome, refers to them espousing of the Jews in Abraham, at Mount Sinai, and in the times of Christ; and, according to Kimchi, to the three captivities of the Jews, in Egypt, in Babylon, and that in which they now are: and some Christian writers think the mystery of the Trinity is here pointed at; and the sense to be, that all the three divine Persons, Father, Son, and Spirit, would espouse them: but rather it is so often repeated to confirm it, and express the certainty of it, which might, on many accounts, seem a thing incredible.
And thou shall know the Lord; that the Messiah is Jehovah, and that he is their husband; they shall all know him, from the least to the greatest; they shall have a saving knowledge of him, which will issue in eternal life; they shall own him, and acknowledge him, serve and obey him, as their Lord, Head, and Husband, as well as love him, and believe in him.
The Targum is,"and ye shall know to fear before the Lord;''see Jer 31:34. Let it be observed, here are no conditions throughout, it is only "I will", and "thou shalt". hnwmab "in fide", V. L.