  In this paper, we confirm several conjectured congruences of Sun concerning
the divisibility of binomial sums. For example, with help of a quadratic
hypergeometric transformation, we prove that $$
\sum_{k=0}^{p-1}\binom{p-1}k\binom{2k}k^2\frac{P_k}{8^k}\equiv0\pmod{p^2} $$
for any prime $p\equiv 7\mod{8}$, where $P_k$ is the $k$-th Pell number.
Further, we also propose three new congruences of the same type.
