God’s choice of His people is the reason for His abiding by them and not forsaking them. He chose them for His love, and He loves them for His choice. His own good pleasure is the source of their election, and His election is the reason for the continuance of His pleasure in them. It would dishonor His great name for Him to forsake them, since it would either show that He made an error in His choice or that He was fickle in His love. God’s love has this glory, that it never changes, and this glory He will never tarnish.
By all the memories of the Lord’s former lovingkindnesses let us rest assured that He will not forsake us. He who has gone so far as to make us His people will not undo the creation of His grace. He has not wrought such wonders for us that He might leave us after all. His Son Jesus has died for us, and we may be sure that He has not died in vain. Can He forsake those for whom He shed His blood? Because He has hitherto taken pleasure in choosing and in saving us, it will be His pleasure still to bless us. Our Lord Jesus is no changeable lover. Having loved His own, He loves them to the end.
[from Faith’s Checkbook by Charles H. Spurgeon]