In the hadeeth narrated by Abu Humayd,
“… and when he raised his head, he stood straight until each bone in his back returned to its place.”
The meaning of, “to its place,” can mean its place before bowing or before beginning the prayer. If we were to say it means before bowing, then after the bowing the person should be holding his hands, because he was doing so before the bowing, placing his hands on his chest. Then, he would grab his knees while bowing and raise his head from bowing and hold his hands and this is the best manner and what was mentioned in the hadeeth narrated by Waa’il ibn Hujr. If we were to say that,
“… until each bone in his back returned to its place,”
means its place before beginning the prayer, the meaning would be that the person drops his hands down by his side after rising from the bowing, because he was not holding his hands before the prayer. Thus, some scholars said that he should not hold his hands after bowing, rather they claim it to be an innovation. The correct opinion is that he hold his hands after the bowing, and the words,
“… until each bone in his back returned to its place,”
refer to before the bowing, and that is the closest to the correct opinion.