Isaiah 56:4

For thus saith the Lord unto the eunuchs that keep my sabbaths,
&c.] That fear and serve the Lord; religiously observe all times of divine worship, and walk in all the commandments and ordinances of the Lord; show regard to all the institutions of the Gospel, and perform all religious exercises, private and public, on Lord's days, and at other times: and choose the things that please me;
who do that which is wellpleasing unto God, which he has declared in his word to be acceptable to him; and do that from right principles, with right views, and of choice; not forced to it by those who have authority over them, or led to it merely by example and custom: and take hold of my covenant;
not the covenant of circumcision, as Kimchi; for what had eunuchs to do with that? but the covenant of grace, the everlasting covenant, the covenant of peace before spoken of ( Isaiah 14:10 ) ( 55:3 ) , made between the Father and the Son, on account of the elect; which may be said to be taken hold of when a person by faith claims his interest in God as his covenant God; comes to Christ as the Mediator of the covenant; and deals with his blood, righteousness, and sacrifice, for pardon, justification, and atonement; regards all the promises and blessings of the covenant as belonging to him and lives by faith on them, as such; so David by faith laid hold on this covenant, ( 2 Samuel 23:5 ) .