In plain words
The reason is that he is filled to the brim with bad thoughts. We must put away bad thoughts of this kind. This age of yours is a very sacred age. We must develop the faith that whatever we do to anyone comes back to us. Only when there is such faith shall we refrain from doing harm to others. If we say, ‘We will do now what we have to do; we will see later when it comes back,’ that becomes very tāmasic. It takes shape purely as rajoguṇa. The birthplace of both lust and anger is rajoguṇa itself. This rajoguṇa destroys man. Through pure sāttvic thoughts we must become sāttvic human beings. This alone is true education. Only when we learn this education do we follow the right path in the learning of the Ātma, and even in mere worldly learning. The blending of the two, education and tapas, is true divinity. What is tapas? To make these three one is tapas. Going off to a forest somewhere, sitting in some cave and thinking of God: that alone is not tapas. To make the three guṇas one and lead them into divine feelings is tapas. If the three guṇas are not made one in this way, it turns into tamas. So we are not embodiments of tamas; we must be embodiments of tapas. We must practise, without ceasing, the tapas of good thoughts. The very heat of those good thoughts must turn into tapas. So we must take these good thoughts as our very ground and hold them as dear as life. We must shape them into good thoughts. At no time must we think of doing anyone ill or harm. That is why: harm no one, or you will come to harm. If we keep wishing ill on others, ill comes to us too. When we take a ball and hit it hard against a wall, the ball comes back as hard as we hit it. When we keep pointing out someone's fault, three faults point back at us. When you point at a man with one finger, saying, ‘He is bad,’ three fingers point back, saying, ‘You are bad.’ We must recognise this truth well and act on it. Being bad in three ways yourself, you try to point out a single fault in others. There are more faults in you than in the one you point at. It is the one with more faults who looks for the faults of others. We must recognise this truth well.