Look upon us. Peter doth not thus speak before he be certain of the purpose and intent of God. And surely in these words he commandeth him to hope for some singular and unwonted benefit; yet here may a question be moved, whether they had power to work miracles so often as they would? I answer, that they were ministers of God's power in such sort, that they did attempt nothing of their own will or proper motion, but the Lord wrought by them, when he knew that it was expedient it should be so. Hereby it came to pass that they healed one and not all. Therefore, as in other things, they had the Spirit of God to be their guide and director, so also in this point. Therefore, before such time as Peter commandeth the lame man to arise, he did east and fasten his eyes upon him; this steadfast looking upon him was not without some peculiar motion of the Spirit. Hereby it cometh to pass that he speaketh so surely (and safely, without all fear) of the miracle. Furthermore, he meant by this word to provoke the lame man to receive the grace of God; yet doth he look for nothing but for an alms.

Fastening his eyes - The word used here denotes "to look intently, or with fixed attention." It is one of the special words which Luke uses (Luke 4:20; Luke 22:56; Acts 1:10; Acts 3:12; Acts 6:15; Acts 7:55; Acts 10:4; etc.) 12 times in all. It is used by no other writer in the New Testament, except twice by Paul, 2-Corinthians 3:7, 2-Corinthians 3:13.
Look on us - All this Was done to fix the attention. He wished to call the attention of the man distinctly to himself, and to what he was about to do. It was also done that the man might be fully apprised that his restoration to health came from him.

Look on us - He wished to excite and engage his attention that he might see what was done to produce his miraculous cure, and, it is likely, took this occasion to direct his faith to Jesus Christ. See note on Acts 3:16 (note). Peter and John probably felt themselves suddenly drawn by the Holy Spirit to pronounce the healing name in behalf of this poor man.

And Peter fastening his eyes upon him,.... Or looking very wistly and intently at him, being, no doubt, under some uncommon impulse of the Spirit of God to take notice of him, and cure him of his disease:
with John; who was also under a like impulse at the same time; and who was equally concerned in this cure, as appears by the notice the man, when healed, took of the one, as well as the other; and by Peter's declaration, Acts 3:11 as also by the following words:
said, look on us; which was said to raise his attention to them, to put him upon observing what manner of men they were, and how unlikely to perform the following cure, and to take notice of the manner in which it would be done. The Jews speak of a supernatural cure effected in such a manner, using such words; and which perhaps is told, with a view to lessen the glory of this (z).
"Elias appeared to one in the likeness of R. Chiyah Rabbah; he said to him, how does my Lord do? he replied to him, a certain tooth distresses me; he said to him, , "look on me"; and he looked on him, and put his finger on it, and he was well.''
(z) T. Hieros. Cetubot, fol. 35. 1.

Peter fastening his eyes on him with John, said, Look on us. And he gave heed--that, through the eye, faith might be aided in its birth.