This essay pictures Manu's Shadow in the ‘in vogue’ Bhagvad-Gita’s chapter 3, karma yoga 'n in chapter 8, akshara parabrahma yoga.

When I thought I am done with the study of interpolations in the Gita after my critique, Inane Interpolations in Bhagvad-Gita (An Invocation for their Revocation) I was tempted to turn my attention to the seldom read but much maligned Manu Smriti*. While I found that that testament is Incongruent and its motivated castigation is nothing but flogging a dead horse riding a blind donkey (an eponymous essay is due on this aspect), nevertheless, I could discern Manu’s shadow on the Gita’s path that is sought to be placed here for a public view.
It is worth noting that at the end of each of its eighteen chapters, it is asserted in the Gita that it is the quintessence of the Upanishads and the Brahmasutrās, and as argued in my critique supra, one-hundred and ten verses in it are latter-day interpolations bereft of the Upanishadic and Brahmasutric connotations. What is more, while some of those smear its inclusive philosophy with sectarian postulations, which echo Manusmritic caste discriminations that are inimical towards some sections of Hindus to their chagrin, the others are ceremonial exhortations that are irrelevant to the subject matter of Gita’s philosophical discourse and thus are seemingly out of place.
Moreover, in the ‘in vogue’ Bhagvad-Gita’s philosophical discourse are found some ritualistic postulations in chapter 3, titled karma yoga, which, are nothing but innovations of Manu’s stipulations in that regard.
It may be noted that it is postulated in the Manu Smriti that -
3.74. Ahuta (not offered in the fire) is the muttering (of Vedic texts), Huta the burnt oblation (offered to the gods), Prahuta (offered by scattering it on the ground) the Bali offering given to the Bhutas, Brahmya-huta (offered in the digestive fire of Brahmanas), the respectful reception of Brahmana (guests), and Prasita (eaten) the (daily oblation to the manes, called) Tarpana.
3.75. Let (every man) in this (second order, at least) daily apply himself to the private recitation of the Veda, and also to the performance of the offering to the gods; for he who is diligent in the performance of sacrifices, supports both the movable and the immovable creation.
3.76 An oblation duly thrown into the fire, reaches the sun; from the sun comes rain, from rain food, therefrom the living creatures (derive their subsistence)
3.117. Having honoured the gods, the sages, men, the manes, and the guardian deities of the house, the householder shall eat afterwards what remains.
3.118. He who prepares food for himself (alone), eats nothing but sin; for it is ordained that the food which remains after (the performance of) the sacrifices shall be the meal of virtuous men.
Now turning to the Bhagvad-Gita ‘As It Is’, it can be seen that the following verses are reflective innovations of the above that can be taken as inane interpolations.
3.9. Man is not attached to his actions performed in ritualistic sacrifices but all other actions bind him.
3.10. The Creator wanted mankind to prosper through sacrifices, which shall be the milch cow of man’s desires.
3.11. Foster the gods through sacrifices
3.12. Fostered by sacrifices, gods would bestow desired enjoyments, but they are thieves who do not return anything to them (gods).
3.13. Those that partake the remnants of sacrificial food are sinless.
3.14. Food that sustains mankind comes from rains, which are but the outcome of sacrificial ceremonies.
3.15. Brahma is seated in sacrifice.
3.16. Who follow the above regimen would attain moksha.
Besides, as can be seen hereunder, Gita’s Cycle of Creation, in chapter 8, akshara parabrahma yoga, follows Manu’s course.
Manu’s Creative process has it that –
1.52. When that divine one wakes, then this world stirs; when he slumbers tranquilly, then the universe sinks to sleep.
1.57. Thus he, the imperishable one, by (alternately) waking and slumbering, incessantly revivifies and destroys this whole movable and immovable (creation).
1.67. A year is a day and a night of the gods; their division is (as follows): the half year during which the sun progresses to the north will be the day, that during which it goes southwards the night.
1.68. But hear now the brief (description of) the duration of a night and a day of Brahman and of the several ages (of the world, yuga) according to their order.
1.69. They declare that the Krita age (consists of) four thousand years (of the gods); the twilight preceding it consists of as many hundreds, and the twilight following it of the same number.
1.70. In the other three ages (Treta Yuga, Dvapara Yuga, and Kali Yuga) with their twilights preceding and following, the thousands and hundreds are diminished by one (in each).
1.71. These twelve thousand (years)* which thus have been just mentioned as the total of four (human) ages, are called one age of the gods. (*ten-thousand normal and two-thousand twilights)
1.72. But know that the sum of one thousand ages of the gods (makes) one day of Brahman, and that his night has the same length.
1.73. Those (only, who) know that the holy day of Brahman, indeed, ends after (the completion of) one thousand ages (of the gods) and that his night lasts as long, (are really) men acquainted with (the length of) days and nights.
Here’s the Gita’s Cycle of Creation in Manu’s track supra-
8. 17
Wise all realize days Brahman
Ages thousands make with nights.
8.18
By day as He brings beings
Un-manifests He all by night.
8.19
It’s all rebirths through His day
But with nightfall cease they all
As He wakes up puts He back.
(Above verses are excerpts from the author’s Bhagvad-Gita: Treatise of Self-help)
*The Laws of Manu by G. Buhler, Oxford at the Clarendon Press, 1886, available at Internet Archive