Why is there still no need to grieve? This is being given here in this verse. For one who is born death is certain when the results of the actions which originated it are exhausted. Similarly when one dies rebirth is indeed certain due to the reactions good or bad which one has to accept by the karmic actions accrured while one was in that physical body. Therefore for the inevitable fact of birth and death one should never subject oneself to lament for.

Why should one not grieve? Because a natural function is being enacted according to cosmic order.

Now begins the summation.

Therefore understanding the reality of the existence of birth and death there should be no delusion.

It is evident that death of the physical body is inevitable to whatever is born and that there is no way to escape from this physical termination of the body. Similarly rebirth is unavoidable once one's physical body has died. How can something which has been lost become again? It is conceivable that something which has already been to become again; but it is inconceivable for that which has never been to become. Therefore there is nothing that can come that has not been. What is known as birth and death is but just different modifications of an ever existing condition. Yarn and other materials exist but when they are woven into a fabric that is a particular arrangement of the yarn itself, it receives the name cloth in its modified state. Even the asat-karya-vadis who follow the fallacious hypothesis that existence comes from non-existence should admit the ever existing state, for what we know as cloth to them is a new creation but is factually the same old yarn only in a new form which has been created. It is not sagacious or well thought out to assume that a new substance has come into being simply because of a modified condition.

Thus coming into existence and disappearing from existence are modified states of an ever existing reality. One of the conditions of this modified state is its appearance called birth and another condition being its diametric opposite is known as death which by disappearing this ever existing reality passes into. For a substance which is intrinsically metamorphic the process of modification is essential. As in the case of a clod of earth, transformed into clay, transformed into a pot, transformed into dust and transformed back to earth again. The manifestation of a subsequent condition is but a modification of a previous condition and that same subsequent condition becomes a prior condition of another subsequent condition. Reasoning in this way it can be understood that it is natural that successive modifications take place in regards to creation and destruction of physical bodies which cannot be avoided and there is no reason to lament due to this.

If there is some slight grief which may be apparent by the passing from a prior modified state to a subsequent modified state even this grief need not arise in the case of living entities such as human beings because... and the next verse 28 clarifies why.

How is this verse to be understood? For one who is born death is certain. This is because of the reality of a fixed time limit in regard to the continuation of actions relating to the coming into existence of one's physical body as well as the longevity of one's present physical body. The fact that this reality is inevitable is due to the nature of activities performed in one's previous existence which causes one to be continuously connected to the cycle of birth and death in the present body. Therefore it does not behoove one to grieve over the unavoidable regarding the physical body which is dependant on actions.