In plain words
At once he washed the teeth in the Gaṅgā and gave them with his right hand. Kṛṣṇa looked towards Arjuna. Arjuna bowed his head. "Such sacrifice, such devotion to God, such a nature, I have never seen anywhere. Bhakti and surrender like this are not to be seen in any corner of me; Kṛṣṇa, forgive me," he said. Then Kṛṣṇa told him, "Do you know who this Karṇa is? Karṇa was born before your eldest brother Dharmarāja." He was deeply grieved. Why was this not told before? I have tormented my own elder brother in so many ways. Karṇa was greater than Dharmaja.
To be ready like this to give God anything at all: that was the Dharma of those days. Every karma has a result. Every karma is itself a seed. Every seed is itself a tree. On every tree fruits come. The tree gives just such fruits. So we must set about doing holy karmas. As the karmas are, so the results will be. But at the time of doing them we do them happily. But when we go through their results, we go through them with streams of tears. At the very start we must recognise and decide which karmas are good and which karmas are bad, and enter into the good karmas. Today, under the influence of Prakṛti, we do karmas without weighing what comes before and after. We speak words without thinking of what comes before and after. In the end, when the result comes, we are crushed. Every act in the world is nothing but an act of Prakṛti. The rain fell. Did it fall for one man? No. The rain fell for every human being in Prakṛti. It gives coolness to all. It quenches the thirst of all. The breeze from the Malaya hills blows. It is not for one man alone. It is for all living beings. The five elements have come precisely to protect the creatures of Prakṛti. They have not come for any one person. In the same way God too has not come for one race, for one country, for one individual. He has come to uplift the universe. Whatever karmas anyone does, He gives a result to match.
Before we do karmas, we should take some time, think it over, and do good deeds. We must see that no hardship or loss of any kind comes to anyone through these karmas. But in the world this is impossible. If you take on the attachment called being human and then want to do karmas, it will never be possible. Only a person who has forgotten attachment to the body can do this work.