Thank you for your question.
It is certainly possible to see angels and believe them to be men as the following scriptures illustrate.
Hebrews 13:2 Be not forgetful to entertain strangers: for thereby some have entertained angels unawares.
The writer could be referring to the following:
Genesis 18:2 And he lift up his eyes and looked, and, lo, three men stood by him: and when he saw them, he ran to meet them from the tent door, and bowed himself toward the ground,
Lot and the men of Sodom
Genesis 18:1 And there came two angels to Sodom at even; and Lot sat in the gate of Sodom: and Lot seeing them rose up to meet them; and he bowed himself with his face toward the ground; 2 And he said, Behold now, my lords, turn in, I pray you, into your servant’s house, and tarry all night, and wash your feet, and ye shall rise up early, and go on your ways. And they said, Nay; but we will abide in the street all night. 3 And he pressed upon them greatly; and they turned in unto him, and entered into his house; and he made them a feast, and did bake unleavened bread, and they did eat. 4 But before they lay down, the men of the city, even the men of Sodom, compassed the house round, both old and young, all the people from every quarter: 5 And they called unto Lot, and said unto him, Where are the men which came in to thee this night?...
Joshua 5: 13 And it came to pass, when Joshua was by Jericho, that he lifted up his eyes and looked, and, behold, there stood a man over against him with his sword drawn in his hand: and Joshua went unto him, and said unto him, Art thou for us, or for our adversaries? 14 And he said, Nay; but as captain of the host of the LORD am I now come. And Joshua fell on his face to the earth, and did worship, and said unto him, What saith my lord unto his servant?
Manoah and his wife
Judges 13:3 And the angel of the LORD appeared unto the woman, and said unto her, Behold now, thou art barren, and bearest not: but thou shalt conceive, and bear a son...6 Then the woman came and told her husband, saying, A man of God came unto me, and his countenance was like the countenance of an angel of God, very terrible: but I asked him not whence he was, neither told he me his name:...8 Then Manoah intreated the LORD, and said, O my Lord, let the man of God which thou didst send come again unto us, and teach us what we shall do unto the child that shall be born. 9 And God hearkened to the voice of Manoah; and the angel of God came again unto the woman as she sat in the field: but Manoah her husband was not with her. 10 And the woman made haste, and ran, and shewed her husband, and said unto him, Behold, the man hath appeared unto me, that came unto me the other day. 11 And Manoah arose, and went after his wife, and came to the man, and said unto him, Art thou the man that spakest unto the woman? And he said, I am.... 15 And Manoah said unto the angel of the LORD, I pray thee, let us detain thee, until we shall have made ready a kid for thee. 16 And the angel of the LORD said unto Manoah, Though thou detain me, I will not eat of thy bread: and if thou wilt offer a burnt offering, thou must offer it unto the LORD. For Manoah knew not that he was an angel of the LORD. 17 And Manoah said unto the angel of the LORD, What is thy name, that when thy sayings come to pass we may do thee honour? 18 And the angel of the LORD said unto him, Why askest thou thus after my name, seeing it is secret? 19 So Manoah took a kid with a meat offering, and offered it upon a rock unto the LORD: and the angel did wondrously; and Manoah and his wife looked on. 20 For it came to pass, when the flame went up toward heaven from off the altar, that the angel of the LORD ascended in the flame of the altar. And Manoah and his wife looked on it, and fell on their faces to the ground. 21 But the angel of the LORD did no more appear to Manoah and to his wife. Then Manoah knew that he was an angel of the LORD.
Angels when they choose to be seen can disclose or hide their glory at will as can be seen from the resurrection accounts.
Matthew 28:2 And, behold, there was a great earthquake: for the angel of the Lord descended from heaven, and came and rolled back the stone from the door, and sat upon it. 3 His countenance was like lightning, and his raiment white as snow: 4 And for fear of him the keepers did shake, and became as dead men.
Mark 16:5 And entering into the sepulchre, they saw a young man sitting on the right side, clothed in a long white garment; and they were affrighted.
Luke 24:4 And it came to pass, as they were much perplexed thereabout, behold, two men stood by them in shining garments: 5 And as they were afraid, and bowed down their faces to the earth, they said unto them, Why seek ye the living among the dead?
John 20:11 But Mary stood without at the sepulchre weeping: and as she wept, she stooped down, and looked into the sepulchre, 12 And seeth two angels in white sitting, the one at the head, and the other at the feet, where the body of Jesus had lain. 13 And they say unto her, Woman, why weepest thou? She saith unto them, Because they have taken away my Lord, and I know not where they have laid him.
At the ascension
Acts 1:10 And while they looked stedfastly toward heaven as he went up, behold, two men stood by them in white apparel; 11 Which also said, Ye men of Galilee, why stand ye gazing up into heaven? this same Jesus, which is taken up from you into heaven, shall so come in like manner as ye have seen him go into heaven.
The conclusion is that if we see an angel we will believe him to be a man unless he chooses to enlighten us as part of God’s plan and purpose. Speculation is valueless. Further it is not to be supposed that an angel’s normal mode of moving from place to place involves walking down the street (unless being seen to walk down a street has a purpose).
I hope this helps.
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