Adam Clarke on Nehemiah 1:4

And mourned certain days - From the month Chisleu to the month Nisan; about four months from the time he received the above information, till the time that Artaxerxes noticed his grief, Neh 2:1. All this time he probably spent in supplication to God; waiting for a favorable opening in the Divine providence. Every good work is not to be undertaken hastily; prayer and watchfulness are necessary to its completion. Many good works have been ruined by making haste.