His seed shall endure for ever,.... This is a confirmation by his oath of what he had before said, Psa 89:29 which may be understood either of the perseverance of particular believers, of everyone of the spiritual seed of Christ; or of the duration of the church in general, throughout all ages, as before observed; and these being matters of moment and importance, and of which there are sometimes doubts in the minds of the Lord's people about them, and that they may be firmly believed by them, he confirms them with an oath; for God never swears to trivial things; and when he does swear, it is to remove the doubts of his people, and make their minds easy: and his throne as the sun before me; that is, shall continue as long as it does; see Psa 89:29, or shall be bright, splendid, and glorious as the sun, so the Targum, "and his throne light as the sun before me;'' meaning his church and kingdom, of which the throne is an emblem, and which became so in Gospel times, clear and lucid as the sun, Sol 6:10, when day was made by the rising of the sun of righteousness, and by the bright shining of the Gospel ministry; and at particular periods since, as in the times of Constantine, when the church was clothed with the sun, and at the Reformation, when Christ appeared with a rainbow on his head, and his face was as the sun, Rev 12:1 and especially this will be the case of the church in the latter day, when the light of the moon will be as the light of the sun, and the light of the sun seven fold, as the light of seven days; and when the city, the church, will stand in no need of the sun, nor of the moon; and also in the ultimate glory, when the saints will shine as the sun in the kingdom of God; see Isa 30:26. This passage is applied to the Messiah by the Jews (a). (a) Zohar in Gen. fol. 30. 1.