﴿ وَلَا عَلَى ٱلَّذِينَ إِذَا مَآ أَتَوْكَ لِتَحْمِلَهُمْ قُلْتَ لَآ أَجِدُ مَآ أَحْمِلُكُمْ عَلَيْهِ تَوَلَّوا۟ وَّأَعْيُنُهُمْ تَفِيضُ مِنَ ٱلدَّمْعِ حَزَنًا أَلَّا يَجِدُوا۟ مَا يُنفِقُونَ ﴾

“Nor [shall blame attach] to those who, when they came unto thee [O Prophet, with the request] that thou provide them with mounts, were told by thee, "I cannot find anything whereon to mount you" - [whereupon] they turned away, their eyes overflowing with tears out of sorrow that they had no means to spend [on their equipment].”

Please check ayah 9:93 for complete tafsir.