The permissibility of taking one or two steps while praying, and that is not disliked if done for a reason. The permissibility of the Imam praying in a place that is higher than the people praying behind him, if that is done for a reason, such as teaching them how to offer prayers, and other than that.

Sahih Muslim · Book 5 · Hadith 544 a

حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، وَقُتَيْبَةُ بْنُ سَعِيدٍ، كِلاَهُمَا عَنْ عَبْدِ الْعَزِيزِ، قَالَ يَحْيَى أَخْبَرَنَا عَبْدُ الْعَزِيزِ بْنُ أَبِي حَازِمٍ، عَنْ أَبِيهِ، أَنَّ نَفَرًا، جَاءُوا إِلَى سَهْلِ بْنِ سَعْدٍ قَدْ تَمَارَوْا فِي الْمِنْبَرِ مِنْ أَىِّ عُودٍ هُوَ فَقَالَ أَمَا وَاللَّهِ إِنِّي لأَعْرِفُ مِنْ أَىِّ عُودٍ هُوَ وَمَنْ عَمِلَهُ وَرَأَ…

Abu Hazim is reported on the authority of his father: Some people came to Sahl b. Sa'd and began to differ about the wood of which the (Prophet's pulpit was made. He (Sahl b. Sa'd) said: By Allah, I know of which wood it…