The LORD is thy keeper: the LORD is thy shade upon thy right hand.  Ps 121:5

Two principal points are asserted in these previous words. 
1.  Jehovah, and Jehovah alone, the omnipotent and self-existent God, is the Keeper, and Preserver of his people.  2.  The people of God are kept, at all times and in all circumstances, by his mighty power unto everlasting salvation; they are preserved even “for evermore.”  In the first particular, the divinity of the great Keeper is declared; and, in the second, the eternal security of his people through his omnipotence and faithfulness.  This was the Psalmist’s gospel.  He preached it to others, and he felt it himself.  He did not speculate upon what he did not understand; but he had a clear evidence, and a sweet perception, of these two glorious doctrines, which he delivered to the people.......This character, under the name of Jehovah, is the character of Christ.  Just such a one is Jesus, the Shepherd of Israel.  He says of himself to the Father,  “Those that thou gavest me I have kept, and none of them is lost, but the Son of Perdition, that the Scripture might be fulfilled.” .....From what has been premised, it seems evident, that the keeper of the faithful is no other than Jehovah.  This the Psalmist has proved.  It appears equally evident that Christ is their Keeper and Preserver.  This he hath declared himself; and his apostles have repeatedly declared it of him.  It follows, therefore, that Christ is truly and essentially Jehovah.  All the sophistry in the world cannot elude this conclusion; nor all the heretics in the world destroy the premises.  And, if Christ be Jehovah, he is all that supreme, eternal, omnipotent being, which Arians, Socinians, and others deny him to be.
                                                                                                                                          Ambrose Serle