وَٱللَّهُ أَعْلَمُ بِأَعْدَآئِكُمْ ۚ وَكَفَىٰ بِٱللَّهِ وَلِيًّا وَكَفَىٰ بِٱللَّهِ نَصِيرًا
Wallaahu a'lamu bi a'daaa'i-kum; wa kafaa billaahi waliyyanw wa kafaa billaahi naseera
God knows your enemies best: God is enough to protect and to help you.
God knows your enemies best. God is sufficient as a protector, and God is sufficient as a helper.
The reassurance sits between two verses describing people who want the community to go astray, and it answers them with names rather than instructions. Kafā bi-llāhi is said twice in one breath, once for walī, the one who stands close and takes charge of your affairs, and once for naṣīr, the helper who arrives when aid is needed. The verse calls them your enemies, and puts God's knowledge of them above yours.