It is narrated from Sayyiduna Abu Umamah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "None of you should come to the prayer while holding back his urine until he has relieved himself."
"And whoever puts his eyes (by peeping) into a house without the permission of its people has brought ruin upon himself."
"And whoever leads a people in prayer and singles himself out in supplication, leaving them out, has betrayed them."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 7476