Destruction, Destroyer, Messenger of God, or God Himself?

Translation team moved into the translation of the Passover. There are a lot of movies out there showing how the Passover event happened. One of my favorites is an animation film called "Prince of Egypt." There a vague light comes into the scene from the sky and go around the houses, checking if there is a blood on the doorposts. If there is, the light goes around it, and if there isn't, it goes in and kills the first born male in that house. Here, in Exodus 12:23, Moses is announcing to the leaders of the community of Israel what he heard from the Lord.

Exo. 12:23 For the LORD will pass through to strike down the Egyptians; when he sees the blood on the lintel and on the two doorposts, the LORD will pass over that door and will not allow the destroyer to enter your houses to strike you down. (NRSV)

It says 'destroyer.' Who is this 'destroyer'?
The translation team has not even think about this question, but came to certain conclusions: two translators interpreted as an Angel. It is quite clear because he signed (sign language) obvious 'angel', one translator just skipped this word and let the Lord be the one doing the direct action of killing the first born (obviously, he thought it was not an important information...).

In Hebrew
‏וְעָבַ֣ר יְהוָה֮ לִנְגֹּ֣ף אֶת־מִצְרַיִם֒ וְרָאָ֤ה אֶת־הַדָּם֙ עַל־הַמַּשְׁק֔וֹף וְעַ֖ל שְׁתֵּ֣י הַמְּזוּזֹ֑ת וּפָסַ֤ח יְהוָה֙ עַל־הַפֶּ֔תַח וְלֹ֤א יִתֵּן֙ הַמַּשְׁחִ֔ית לָבֹ֥א אֶל־בָּתֵּיכֶ֖ם לִנְגֹּֽף׃

המשחית‏ is the word here causing a bit of problem. This word is a articular participle, and the participle is Hiphil participle masc.sg.abs. There are basically two ways to understand this construction here: 1) the one who does the action (of destruction), or 2) the concept itself (i.e. the destruction). Many of the translations go with the first interpretation.

It is obvious from the other verses that it, killing of the first born, was the LORD's doing. If so, separate denotation to the destroyer makes things confused. If LORD = the Destroyer, then the LORD is not allowing/permitting Himself to enter into the houses of the sons of Israel to strike... funny.

For me, the easiest understanding is to take this articular hiphil participle as an abstract concept, i.e., 'destruction', since the destruction is the Lord's doing but the Lord watches ('vigil', in later passage) to keep the 'destroyer' out of the houses of the sons of Israel sounds like there is an opposing being against the Lord... Anyways, ancient Hebrew worldview must be investigated to answer this question... I have to e-mail many people.