After these things came the word of Yahweh unto Abram, in a vision、 saying,— Do not fear、 Abram, I am a shield to thee, thine exceeding great reward.” (Genesis 15:1, EMPH)

A shield is a weapon of defense, in this case it is a small shield, one that would be maneuverable and easy to wield, although one suspects that this kind of shield is all that Abraham had in his household since he didn’t routinely make battle, nor have a standing army.

The takeaway seems to be that the Lord is watching out for Abraham.  In context this comes just after Lot had been captured and carried off and Abraham and the men of his household go after the brigands and free Lot and recapture all that the robbers had stolen.  In the aftermath, the Lord vows that he will stand as a shield to Abraham and by extension to all that Abraham owned.

It’s interesting that Abraham follows this statement immediately with a comment about his lack of any son to be his heir, as if Abraham is saying, “it’s well and good that you are a shield, Lord, but what about your promise of an heir?”  The Lord promises again that Abraham will have an actual son who will be his heir.

Abraham is our spiritual father and if the Lord was a shield to Abraham, then he is a shield to us as well.  God is as good as his word.  We see this in the life of Abraham and if we look carefully we will see it in our own lives as well.