It is narrated from Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "There are two steps: one of them is greatly beloved to Allah and the other is greatly disliked. The step that is beloved to Allah is that a man sees a gap in the row and fills it. And the step that Allah greatly dislikes is that when a man (in prayer) is about to stand up, he puts his right leg forward, places his hand upon it, keeps the left one where it is, and then stands up."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3569