[ Abdullah Yusuf Ali ]
Behold, they entered his presence, and said: "Peace!" He said, "Peace!" (and thought, "These seem) unusual people."
[ Saheeh International ]
When they entered upon him and said, "[We greet you with] peace." He answered, "[And upon you] peace, [you are] a people unknown.
5006 They were angels, who appeared suddenly before him at his tent door in the guise of men, and saluted him with the salutation of peace. He returned the salutation, but felt, from their appearance and their manner, that they were unusual, not ordinary, strangers.
5007 Munkar, unknown, uncommon, unusual, not customary, (hence by derived meaning, not applicable here, not fair or just): opposite in both primary and secondary meanings to ma'ruf, well-known, usual, customary, just. Cf. 15:62.