Charles Haddon Spurgeon said this quote

Prayer is never out of season: in summer and in winter its merchandize is precious. Prayer gains audience with heaven in the dead of night, in the midst of business, in the heat of noonday, in the shades of evening. In every condition, whether of poverty, or sickness, or obscurity, or slander, or doubt, your covenant God will welcome your prayer and answer it from His holy place.