Whenever we dream of a spider, it symbolizes suspicion that had no basis. This means whatever we suspected to be wrong or was suspicious about was not wrong and it was authentic. Based on this, it appears that there was nothing wrong with the teaching that you listened to or watched on television (the parts that you were suspicious about).
In dreams and visions, the number two symbolizes agreement and union. The number two is the number of witness and testimony. It speaks of unity in this sense. The fact that there were two spiders speaks of either you being very sure (double) that the teaching was wrong or you and another person agreeing that the teaching was wrong. This speaks of two people agreeing that something is wrong but because it was spiders, it was actually not wrong.
A towel is a piece of absorbent fabric used for drying or wiping a body or a surface. This is the final step to clean ourselves or whatever was cleaned. In this case, it symbolizes the cleansing or purification of a teaching. It was white which also symbolizes purity or authentication (teachings). This part symbolizes that you are very careful to make sure that the teaching is in fact correct.
The fact that the symbol of a swimming pool is present in the dream, speaks of the fact that the teaching that you were suspicious about was probably about financial or spiritual blessings in the church or in our lives, or about the workings and gifts of the Holy Spirit in the church or in our lives. The fact that there was a diving board indicates that this had to do with the Holy Spirit. It speaks of us enjoying the water (Holy Spirit) as when people dive into it or playing in the water. It speaks of us enjoying the Holy Spirit (gifts and workings of the Holy Spirit). Spiritual blessings are also part of this.
Please let me know if you have any questions.