Ref. No. 991/41-145
In the name of Allah the most Gracious the most merciful
The answer to your question is as follows:
Performing the prayer in congregation with the rows tight and close together is sunnat and it is much emphasized in many Ahadith. The prophet of Allah (saws) is reported to have said “"Straighten your rows and stand close to each other." (Abu Dawood)
Nevertheless, the above mentioned narration and alike relates to the normal circumstances. The ruling may differ under abnormal atmospheres. Therefore, today due to the covid-19 pandemic, we have to follow the government order in a bid to stem the epidemic virus, and thus standing in rows keeping gap within ourselves just as long as the epidemic persists.
It is reported that once Hazrat Abu Bakrah (ra) got to masjid when the prophet of Allah (saws) was in the state of ruku. Following the prophet he bent in ruku and then joined the rows. When the prophet of Allah (saws) knew it, he said: May Allah increase your enthusiasm, but do not ever repeat it. (Bukhari)
Hence, in normal atmosphere performing prayerskeeping gaps within rows is MakroohTahreemi (strongly disliked).
In today’s time when the cases of covid-19 pandemic are raising rapidly, in light of the social distancing guidelines of the government, health organizations instructions and directions of physicians, if congregational prayers are performed keeping spaces between the rows, the prayer will still be valid. Hadith says: لا ضرر ولا ضرار (ابن ماجہ)
And Allah knows best
Darul Uloom Waqf Deoband