مَا جَاءَنَا مِنْ بَشِيرٍ
No bearer of good news has come to us.
In this expression, «ما» negates the event, «من» reinforces the negative construction, and «بشير» is an indefinite noun. The result excludes the arrival of any individual of that category, not just one identified individual.
This is universality in negation. The added «من» strengthens the scope of denial; in this construction it should not be translated as an ordinary “from.”