One thing that impressed- and maybe even startled- me about Buddhism early on was that one should be skeptical of everything. Questioning and debate about spiritual topics is allowed, and even encouraged. I also often found this sentiment reflected in speaking to Venerable Sik Ji Xing, who in teaching us about 'daily practice' emphasized many times, 'Don't believe me. See for yourself.' I find this perspective highly refreshing, and believe it greatly encourages positive spiritual development.