al-Tawba 9:7

Kayfa yakūnu li'l-mushrikīna ʿahdun ʿinda'llāhi wa ʿinda rasūlihī illa'lladhīna ʿāhadtum ʿinda'l-masjidi'l-ḥarām; fa-ma'staqāmū lakum fa'staqīmū lahum; inna'llāha yuḥibbu'l-muttaqīn

"How can the mushrikūn have a treaty with God and with His Messenger — except those with whom you made a treaty at al-Masjid al-Ḥarām. So long as they are straight with you, be straight with them. God loves those who guard themselves."

There was an exception in the fourth verse; the seventh lays down a second. And the measure of this second exception is different: the place where the treaty was made.

I record this as an observation: the block holds two separate sections of the party bearing the same name outside the ruling. The sūra breaches its own category twice.

The construction of the sentence must be recorded, and it is the very structure treated in al-Anfāl at 8/61.

Form X of the root ق-و-م: istiqāma — to stand straight, not to bend.

And on both sides the same verb is used, in the same form:

The same symmetry was recorded in al-Anfāl at 8/61: in janaḥū li'l-salmi fa'jnaḥ lahā — "if they incline to peace, incline to it too." The measure recorded there holds here as well: the response is given with the same verb and in the same form. I rely on that treatment.

I record this as my own reading, and its ground is the overlap of the verbs in the two verses: the Qurʾān builds the treaty relation on reciprocity — and it shows the reciprocity by means of the language itself, laying the same verb on both sides.

And the particle mā must be dwelt on: fa-mā staqāmū lakum — here mā states time: "so long as they are". The obligation, that is, continues together with the conduct of the other side.