وَتَوَاصَوْا بِالْحَقِّ وَتَوَاصَوْا بِالصَّبْرِ
And they counsel one another to truth and counsel one another to patience.
Repetition of tawāṣaw identifies two related yet distinguishable mutual duties: counsel in truth and counsel in perseverance.
The movement proceeds from individual faith and deeds toward shared responsibility. Compressing the two phrases into an undifferentiated synonym would hide the reason the discourse names both.