Why did the disciples deny Jesus (as) and not resist his arrest?

They did not resist precisely because they loved Jesus (as) and followed his teaching not to meet force with force. They proved their faithfulness later, when they chose death rather than give up their faith.

The question assumes that true love would have to show itself through force. But Jesus (as) had taught his disciples something different. If someone strikes you on the right cheek, turn to him the other also. Do not meet force with force.

When soldiers and opponents came to arrest Jesus (as), he himself did not resist. Had the disciples taken up arms, they would have acted against his own teaching, and at the most critical moment. Their restraint was therefore not a sign of weakness but of obedience. They did what their master had told them to do.

That one of them denied him that night and another fled concerns only two out of twelve. People can falter in a moment of fear. What matters is how they act afterwards.

After the crucifixion the disciples went out to many regions and spread the message without fear. The early history of Christianity records that its followers were thrown to wild beasts and burnt alive, and still did not give up their faith. They had learned this spirit of sacrifice from the disciples.

The Holy Qur’an honours the disciples as helpers in the cause of God. Their faithfulness showed itself not in fighting with the sword, but in patience and steadfastness.