The famous verse which is generally used by this anti-devotional people is to prove that Vedas doesn't talk about worship of any deity is " na tasya pratimA asti, yasya nAma mahat yasha:"(He, whose glory knows no bounds, has no images-VAjasanEyi Samhita of Shukla Yajur Veda). This is fortified by another quote, which specifically denies the Supreme Being a body-" na tasya kAryam karaNam cha vidyatE".
But they don't know that In arriving at the true purport of Veda vAkyAs, the aid of upabrahmanas (clarificatory and supportive texts) like ItihAsAs ( Srimad Ramayana and Sri Mahabharata) and PurANAs (like the Sri Vishnu PuranaBhagavatm), is indispensable. No scriptural text can be taken in isolation and its meaning arrived at on that basis. The Veda Purusha himself is reported to be afraid of those who misinterpret the Shruti based merely on superficial study ("bibhEti alpa shrutAt Veda: mAm ayam pratarishyati iti")
The interpretation this atheists place upon the text " na tasya pratimA asti" belongs to the aforesaid category, and is without an appreciation of the true meaning of the word "pratimA". They take it to mean "image" and arrive at the erroneous conclusion that the Lord has no images, and hence deny sanctity to the numerous images of the Lord in various temples, making us all fools worshipping mere stones. Our Acharyas, on the other hand, favour the other meaning of the word, viz., "equal". This leaves us with the more acceptable version, which reads, "He has no equals". In English too, when we say "He is the spitting image of GOpAla", we mean that he is equal in all respects, especially looks, to GOpAla. This interpretation is also more appropriate to the context, considering what follows-"yasya nAma mahat yasha:". The whole sentence would now mean, "He, whose glory knows no bounds, has no equals", which makes eminent sense. And the meaning of "equal" ascribed to the term "pratimA" is quite a popular use.
The Rigveda Samhita (eighth ashtaka, eighth adhyAya, 13th sarga, 3rd khanda) too provides more proof, if further proof were needed, by referring to the wooden image of the Lord which floats in the ocean, unsculpted by human hands, to which the devotee is exhorted to pay obeisance-
"adO yat dAru plavatE sindhO: pArE apourusham
tat Arabhasva durhaNO tEna gaccha parastaram".
Two itihasas Mahabharata and Ramayana also gives reference to deity worship. Now if someone says itihasas are not part of Vedas let me slap in his face by quoting this from upanishad.In the ChāndogyaUpaniṣad (7.1.4), the Purāṇas and Mahābhārata, generally known as histories, are mentioned as the fifthVeda.
when we find Sri Rama worshipping in the temple of Sriman Narayana as a prelude to His Coronation. The night prior to the great event, Sri Raghava, along with Sri Mythily, visits the temple of Sriman Narayana within the palace precincts and, after a purifying bath and with a balanced mind, worships the Lord to His heart's content, offering Him food and partaking of the same as bhagavat prasAdam. Here are the worthy words of Sri Valmiki-
GatE purOhitE Rama: snAtO niyata mAnasa:
saha patnyA VisAlAkshyA NArAyaNam upAgamat.
Pragrihya shirasA pAtreem havishO vidhivat tadA
MahatE daivatAya Ajyam juhAva jvalitE analE."
It is crystal clear from the aforesaid that during Sri Rama's times, there were temples to the Lord, that ritualistic worship was indeed in vogue and the Lord was offered food, which was partaken of by the devotee later as "prasAdam".
Similarly, in Sri Mahabharata too, the BhIshma Parva contains slokas, which comment with wonderment on the occasional strange behaviour of the Lord's images in His temples. It appears that the divine vigrahAs used to shake, roar with laughter, spit blood and fall down by themselves-
"DEvatA pratimAschaiva kampantE hasanti cha
vamanti rudhiram cha asyai: svidyanti prapatanti cha"
hope this will help.