Worshipping the Supreme Lord with a form is an offence in ISLAM and Christianity. Why is the Supreme Lord worshipped in a form in the Vedic Culture?

Every living entity born in this material world because of his past sins and conditioning. Therefore with this impure mind; it is certainly incorrect to assign a form to the supreme lord on the basis of ones own mental speculation; as the supreme lord true nature is highly exalted and situated beyond ones mental comprehension. But as per the information in the vedic literatures; the vedic seers; on account of severe austerity and penance; thus purified their existence; and thus  with a pure mind were thus able to comprehend the true pure nature of the Supreme lord having a wonderful and beautiful form having 4 stout arms holding a disk, a conchshell, a lotus flower and a club; his bodily colour is that of a dark blue rain cloud; his eyes are like lotus petals; he wears a shining yellow lower garment; and is adorned with exquisite unparalleled gems and jewels; and sports a garland made of tulasi and lotus flowers.
Thus since traditions; the knowledge of this pure and the eternal form of the supreme lord was passed on from generations to generations.