لِمَن شَآءَ مِنكُمْ أَن يَسْتَقِيمَ
Liman shaaa'a minkum ai yastaqeem
for whoever among you wills to walk straight.
The same construction turns up in 74:37, where the one who wills is offered two directions, forward or back. Here a single direction is named, and it arrives as istiqāma, the verb behind the straight road asked for in every prayer, which makes straightness something a person does instead of a place they stand.