For John truly baptized with water, Matthew 3:11; water being of a purifying nature, plentiful, and easy to come by. But ye shall be baptized with the Holy Ghost; his gifts and graces, which were (as water on baptized persons) largely bestowed upon them on the day of Pentecost:
1. That the apostles and all others might be assured of the doctrine of the Gospel.
2. That they might be enabled to fulfil their ministry, and obey our Saviour's commands left with them. Not many days hence; it was but ten days after his ascension; but our Saviour would not prefix a certain day, that they might watch every day.