Sayyiduna Anas bin Malik (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "You have left behind some people in Madinah; you have not covered any journey, nor spent anything, nor crossed any valley, but they are equal partners with you in it."
The Companions (may Allah be pleased with them) said: O Messenger of Allah, how are they with us while they are sitting in Madinah? He (peace and blessings be upon him) said: "Excuse has held them back."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 17820